diff --git a/.travis.yml b/.travis.yml
index 13618a50f5..49e9fdad76 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -24,7 +24,6 @@ services:
 
 matrix:
   include:
-    - python: 2.7
     - python: 3.5
     - python: 3.6
     - python: 3.7
diff --git a/appveyor.yml b/appveyor.yml
index 45c5a8af7a..903abb8df8 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -18,10 +18,6 @@ environment:
 
   matrix:
 
-    - PYTHON: "C:\\Python27-x64"
-      PYTHON_VERSION: "2.7"
-      DISTUTILS_USE_SDK: "1"
-
     - PYTHON: "C:\\Python35-x64"
       PYTHON_VERSION: "3.5"
 
diff --git a/bench/compress_normal.py b/bench/compress_normal.py
index 5dd8113790..e9b3945f4a 100644
--- a/bench/compress_normal.py
+++ b/bench/compress_normal.py
@@ -1,11 +1,14 @@
-import numpy as np
 import sys
-sys.path.insert(0, '..')
-import zarr
-import line_profiler
 import timeit
+
+import numpy as np
+
+import line_profiler
+import zarr
 from zarr import blosc
 
+sys.path.insert(0, '..')
+
 # setup
 a = np.random.normal(2000, 1000, size=200000000).astype('u2')
 z = zarr.empty_like(a, chunks=1000000, compression='blosc', compression_opts=dict(cname='lz4', clevel=5, shuffle=2))
diff --git a/build.cmd b/build.cmd
index ef92badb41..053894d249 100644
--- a/build.cmd
+++ b/build.cmd
@@ -23,9 +23,7 @@ SET COMMAND_TO_RUN=%*
 SET WIN_SDK_ROOT=C:\Program Files\Microsoft SDKs\Windows
 
 SET MAJOR_PYTHON_VERSION="%PYTHON_VERSION:~0,1%"
-IF %MAJOR_PYTHON_VERSION% == "2" (
-    SET WINDOWS_SDK_VERSION="v7.0"
-) ELSE IF %MAJOR_PYTHON_VERSION% == "3" (
+IF %MAJOR_PYTHON_VERSION% == "3" (
     SET WINDOWS_SDK_VERSION="v7.1"
 ) ELSE (
     ECHO Unsupported Python version: "%MAJOR_PYTHON_VERSION%"
diff --git a/docs/conf.py b/docs/conf.py
index 9c128f4c9c..673f4b439b 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -14,27 +14,15 @@
 # serve to show the default.
 
 
-import sys
 import os
-from mock import Mock as MagicMock
-
-
-PY2 = sys.version_info[0] == 2
-
-
-class Mock(MagicMock):
-    @classmethod
-    def __getattr__(cls, name):
-        return Mock()
-
-
-MOCK_MODULES = []
-if PY2:
-    MOCK_MODULES.append('lzma')
-
-
-sys.modules.update((mod_name, Mock()) for mod_name in MOCK_MODULES)
+import sys
 
+# The version info for the project you're documenting, acts as replacement for
+# |version| and |release|, also used in various other places throughout the
+# built documents.
+#
+# The short X.Y version.
+import zarr
 
 # If extensions (or modules to document with autodoc) are in another directory,
 # add these directories to sys.path here. If the directory is relative to the
@@ -81,12 +69,6 @@ def __getattr__(cls, name):
 copyright = '2018, Zarr Developers'
 author = 'Zarr Developers'
 
-# The version info for the project you're documenting, acts as replacement for
-# |version| and |release|, also used in various other places throughout the
-# built documents.
-#
-# The short X.Y version.
-import zarr
 version = zarr.__version__
 # The full version, including alpha/beta/rc tags.
 release = zarr.__version__
diff --git a/docs/release.rst b/docs/release.rst
index 84a6e0853d..4749502344 100644
--- a/docs/release.rst
+++ b/docs/release.rst
@@ -15,6 +15,9 @@ Upcoming Release
   compatibility issue with testing against the Azure Storage
   Emulator. By :user:`alimanfoo`; :issue:`468`, :issue:`467`.
 
+* Removed support for Python 2.
+  By :user:`jhamman`; :issue:`393`, :issue:`470`.
+
 .. _release_2.3.2:
 
 2.3.2
diff --git a/setup.py b/setup.py
index e2367233f5..e586f13aca 100644
--- a/setup.py
+++ b/setup.py
@@ -1,8 +1,7 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import, print_function, division
-from setuptools import setup
 import sys
 
+from setuptools import setup
 
 DESCRIPTION = 'An implementation of chunked, compressed, ' \
               'N-dimensional arrays for Python.'
@@ -17,11 +16,6 @@
     'numcodecs>=0.6.2',
 ]
 
-if sys.version_info < (3, 5):
-    dependencies.append('scandir')
-if sys.version_info < (3, 3) and sys.platform == "win32":
-    dependencies.append('pyosreplace')
-
 setup(
     name='zarr',
     description=DESCRIPTION,
@@ -35,6 +29,7 @@
         'setuptools>18.0',
         'setuptools-scm>1.5.4'
     ],
+    python_requires='>=3.5',
     install_requires=dependencies,
     package_dir={'': '.'},
     packages=['zarr', 'zarr.tests'],
@@ -47,8 +42,6 @@
         'Programming Language :: Python',
         'Topic :: Software Development :: Libraries :: Python Modules',
         'Operating System :: Unix',
-        'Programming Language :: Python :: 2',
-        'Programming Language :: Python :: 2.7',
         'Programming Language :: Python :: 3',
         'Programming Language :: Python :: 3.5',
         'Programming Language :: Python :: 3.6',
diff --git a/tox.ini b/tox.ini
index 2a466b8731..9a296708bf 100644
--- a/tox.ini
+++ b/tox.ini
@@ -4,15 +4,12 @@
 # and then run "tox" from this directory.
 
 [tox]
-envlist = py27, py35, py36, py37-npy{115,116,latest}, docs
+envlist = py35, py36, py37-npy{115,116,latest}, docs
 
 [testenv]
 install_command = pip install --no-binary=numcodecs {opts} {packages}
 setenv =
     PYTHONHASHSEED = 42
-    # hooks for coverage exclusions based on Python major version
-    py35,py36,py37: PY_MAJOR_VERSION = py3
-    py27: PY_MAJOR_VERSION = py2
 passenv =
     ZARR_TEST_ABS
     ZARR_TEST_MONGO
@@ -21,13 +18,13 @@ commands =
     # clear out any data files generated during tests
     python -c 'import glob; import shutil; import os; [(shutil.rmtree(d) if os.path.isdir(d) else os.remove(d) if os.path.isfile(d) else None) for d in glob.glob("./example*")]'
     # main unit test runner
-    py27,py35,py36: pytest -v --cov=zarr --cov-config=.coveragerc zarr
+    py35,py36: pytest -v --cov=zarr --cov-config=.coveragerc zarr
     # don't collect coverage when running older numpy versions
     py37-{npy115,npy116}: pytest -v zarr
     # collect coverage and run doctests under py37
     py37-npylatest: pytest -v --cov=zarr --cov-config=.coveragerc --doctest-plus zarr --remote-data
     # generate a coverage report
-    py27,py35,py36,py37-npylatest: coverage report -m
+    py35,py36,py37-npylatest: coverage report -m
     # run doctests in the tutorial and spec
     py37-npylatest: python -m doctest -o NORMALIZE_WHITESPACE -o ELLIPSIS docs/tutorial.rst docs/spec/v2.rst
     # pep8 checks
@@ -35,10 +32,9 @@ commands =
     # print environment for debugging
     pip freeze
 deps =
-    py27: backports.lzma
     py37-npy115: numpy==1.15.4
     py37-npy116: numpy==1.16.4
-    py27,py35,py36,py37-npylatest: -rrequirements_dev_numpy.txt
+    py35,py36,py37-npylatest: -rrequirements_dev_numpy.txt
     -rrequirements_dev_minimal.txt
     -rrequirements_dev_optional.txt
 
diff --git a/zarr/__init__.py b/zarr/__init__.py
index 55b5016b6d..a35beafa6c 100644
--- a/zarr/__init__.py
+++ b/zarr/__init__.py
@@ -1,20 +1,19 @@
 # -*- coding: utf-8 -*-
 # flake8: noqa
-from __future__ import absolute_import, print_function, division
-
-
-from zarr.core import Array
-from zarr.creation import (empty, zeros, ones, full, array, empty_like, zeros_like,
-                           ones_like, full_like, open_array, open_like, create)
-from zarr.storage import (DictStore, MemoryStore, DirectoryStore, ZipStore, TempStore,
-                          NestedDirectoryStore, DBMStore, LMDBStore, SQLiteStore,
-                          LRUStoreCache, ABSStore, RedisStore, MongoDBStore)
-from zarr.hierarchy import group, open_group, Group
-from zarr.sync import ThreadSynchronizer, ProcessSynchronizer
 from zarr.codecs import *
-from zarr.convenience import (open, save, save_array, save_group, load, copy_store,
-                              copy, copy_all, tree, consolidate_metadata,
-                              open_consolidated)
+from zarr.convenience import (consolidate_metadata, copy, copy_all, copy_store,
+                              load, open, open_consolidated, save, save_array,
+                              save_group, tree)
+from zarr.core import Array
+from zarr.creation import (array, create, empty, empty_like, full, full_like,
+                           ones, ones_like, open_array, open_like, zeros,
+                           zeros_like)
+from zarr.errors import CopyError, MetadataError
+from zarr.hierarchy import Group, group, open_group
 from zarr.n5 import N5Store
-from zarr.errors import CopyError, MetadataError, PermissionError
+from zarr.storage import (ABSStore, DBMStore, DictStore, DirectoryStore,
+                          LMDBStore, LRUStoreCache, MemoryStore, MongoDBStore,
+                          NestedDirectoryStore, RedisStore, SQLiteStore,
+                          TempStore, ZipStore)
+from zarr.sync import ProcessSynchronizer, ThreadSynchronizer
 from zarr.version import version as __version__
diff --git a/zarr/attrs.py b/zarr/attrs.py
index f103650ed6..6c02940c4d 100644
--- a/zarr/attrs.py
+++ b/zarr/attrs.py
@@ -1,9 +1,6 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import, print_function, division
+from collections.abc import MutableMapping
 
-
-from zarr.compat import MutableMapping
-from zarr.errors import PermissionError
 from zarr.meta import parse_metadata
 from zarr.util import json_dumps
 
diff --git a/zarr/codecs.py b/zarr/codecs.py
index 34230de03d..2ccc58f2a6 100644
--- a/zarr/codecs.py
+++ b/zarr/codecs.py
@@ -1,7 +1,4 @@
 # -*- coding: utf-8 -*-
 # flake8: noqa
-from __future__ import absolute_import, print_function, division
-
-
 from numcodecs import *
 from numcodecs.registry import codec_registry
diff --git a/zarr/compat.py b/zarr/compat.py
deleted file mode 100644
index c17142cec3..0000000000
--- a/zarr/compat.py
+++ /dev/null
@@ -1,39 +0,0 @@
-# -*- coding: utf-8 -*-
-# flake8: noqa
-from __future__ import absolute_import, print_function, division
-import sys
-
-
-PY2 = sys.version_info[0] == 2
-
-
-if PY2:  # pragma: py3 no cover
-
-    text_type = unicode
-    binary_type = str
-    reduce = reduce
-    from itertools import izip_longest as zip_longest
-
-    class PermissionError(Exception):
-        pass
-
-    def OrderedDict_move_to_end(od, key):
-        od[key] = od.pop(key)
-
-    from collections import Mapping, MutableMapping
-    from scandir import scandir
-
-
-else:  # pragma: py2 no cover
-
-    text_type = str
-    binary_type = bytes
-    from functools import reduce
-    from itertools import zip_longest
-    PermissionError = PermissionError
-
-    def OrderedDict_move_to_end(od, key):
-        od.move_to_end(key)
-
-    from collections.abc import Mapping, MutableMapping
-    from os import scandir
diff --git a/zarr/convenience.py b/zarr/convenience.py
index 42354d25c3..6e269a10ee 100644
--- a/zarr/convenience.py
+++ b/zarr/convenience.py
@@ -1,20 +1,20 @@
 # -*- coding: utf-8 -*-
 """Convenience functions for storing and loading data."""
-from __future__ import absolute_import, print_function, division
 import io
-import re
 import itertools
-
+import re
+from collections.abc import Mapping
 
 from zarr.core import Array
-from zarr.creation import (open_array, normalize_store_arg,
-                           array as _create_array)
-from zarr.hierarchy import open_group, group as _create_group, Group
-from zarr.storage import contains_array, contains_group
-from zarr.errors import err_path_not_found, CopyError
-from zarr.util import normalize_storage_path, TreeViewer, buffer_size
-from zarr.compat import Mapping, PY2, text_type
+from zarr.creation import array as _create_array
+from zarr.creation import normalize_store_arg, open_array
+from zarr.errors import CopyError, err_path_not_found
+from zarr.hierarchy import Group
+from zarr.hierarchy import group as _create_group
+from zarr.hierarchy import open_group
 from zarr.meta import json_dumps, json_loads
+from zarr.storage import contains_array, contains_group
+from zarr.util import TreeViewer, buffer_size, normalize_storage_path
 
 
 # noinspection PyShadowingBuiltins
@@ -451,9 +451,6 @@ def __exit__(self, *args):
     def __call__(self, *args, **kwargs):
         if self.log_file is not None:
             kwargs['file'] = self.log_file
-            if PY2:  # pragma: py3 no cover
-                # expect file opened in text mode, need to adapt message
-                args = [text_type(a) for a in args]
             print(*args, **kwargs)
             if hasattr(self.log_file, 'flush'):
                 # get immediate feedback
diff --git a/zarr/core.py b/zarr/core.py
index 29d54e4750..d64392c264 100644
--- a/zarr/core.py
+++ b/zarr/core.py
@@ -1,29 +1,28 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import, print_function, division
 import binascii
-import operator
-import itertools
 import hashlib
+import itertools
+import operator
 import re
-
+from functools import reduce
 
 import numpy as np
 from numcodecs.compat import ensure_bytes, ensure_ndarray
 
-
-from zarr.util import (is_total_slice, human_readable_size, normalize_resize_args,
-                       normalize_storage_path, normalize_shape, normalize_chunks,
-                       InfoReporter, check_array_shape, nolock)
-from zarr.storage import array_meta_key, attrs_key, listdir, getsize
-from zarr.meta import decode_array_metadata, encode_array_metadata
 from zarr.attrs import Attributes
-from zarr.errors import PermissionError, err_read_only, err_array_not_found
-from zarr.compat import reduce
 from zarr.codecs import AsType, get_codec
-from zarr.indexing import (OIndex, OrthogonalIndexer, BasicIndexer, VIndex,
-                           CoordinateIndexer, MaskIndexer, check_fields, pop_fields,
-                           ensure_tuple, is_scalar, is_contiguous_selection,
-                           err_too_many_indices, check_no_multi_fields)
+from zarr.errors import err_array_not_found, err_read_only
+from zarr.indexing import (BasicIndexer, CoordinateIndexer, MaskIndexer,
+                           OIndex, OrthogonalIndexer, VIndex, check_fields,
+                           check_no_multi_fields, ensure_tuple,
+                           err_too_many_indices, is_contiguous_selection,
+                           is_scalar, pop_fields)
+from zarr.meta import decode_array_metadata, encode_array_metadata
+from zarr.storage import array_meta_key, attrs_key, getsize, listdir
+from zarr.util import (InfoReporter, check_array_shape, human_readable_size,
+                       is_total_slice, nolock, normalize_chunks,
+                       normalize_resize_args, normalize_shape,
+                       normalize_storage_path)
 
 
 # noinspection PyUnresolvedReferences
@@ -1786,7 +1785,7 @@ def _encode_chunk(self, chunk):
 
     def __repr__(self):
         t = type(self)
-        r = '<%s.%s' % (t.__module__, t.__name__)
+        r = '<{}.{}'.format(t.__module__, t.__name__)
         if self.name:
             r += ' %r' % self.name
         r += ' %s' % str(self.shape)
@@ -1827,11 +1826,11 @@ def info_items(self):
     def _info_items_nosync(self):
 
         def typestr(o):
-            return '%s.%s' % (type(o).__module__, type(o).__name__)
+            return '{}.{}'.format(type(o).__module__, type(o).__name__)
 
         def bytestr(n):
             if n > 2**10:
-                return '%s (%s)' % (n, human_readable_size(n))
+                return '{} ({})'.format(n, human_readable_size(n))
             else:
                 return str(n)
 
@@ -1872,7 +1871,7 @@ def bytestr(n):
                 ('Storage ratio', '%.1f' % (self.nbytes / self.nbytes_stored)),
             ]
         items += [
-            ('Chunks initialized', '%s/%s' % (self.nchunks_initialized, self.nchunks))
+            ('Chunks initialized', '{}/{}'.format(self.nchunks_initialized, self.nchunks))
         ]
 
         return items
@@ -1930,7 +1929,7 @@ def hexdigest(self, hashname="sha1"):
         checksum = binascii.hexlify(self.digest(hashname=hashname))
 
         # This is a bytes object on Python 3 and we want a str.
-        if type(checksum) is not str:  # pragma: py2 no cover
+        if type(checksum) is not str:
             checksum = checksum.decode('utf8')
 
         return checksum
diff --git a/zarr/creation.py b/zarr/creation.py
index 082f4fd3dd..632dd24915 100644
--- a/zarr/creation.py
+++ b/zarr/creation.py
@@ -1,17 +1,16 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import, print_function, division
 from warnings import warn
 
-
 import numpy as np
-
+from numcodecs.registry import codec_registry
 
 from zarr.core import Array
-from zarr.storage import (DirectoryStore, init_array, contains_array, contains_group,
-                          default_compressor, normalize_storage_path, ZipStore)
+from zarr.errors import (err_array_not_found, err_contains_array,
+                         err_contains_group)
 from zarr.n5 import N5Store
-from numcodecs.registry import codec_registry
-from zarr.errors import err_contains_array, err_contains_group, err_array_not_found
+from zarr.storage import (DirectoryStore, ZipStore, contains_array,
+                          contains_group, default_compressor, init_array,
+                          normalize_storage_path)
 
 
 def create(shape, chunks=True, dtype=None, compressor='default',
diff --git a/zarr/errors.py b/zarr/errors.py
index a59318377a..fa3cff04d5 100644
--- a/zarr/errors.py
+++ b/zarr/errors.py
@@ -1,8 +1,4 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import, print_function, division
-
-
-from zarr.compat import PermissionError
 
 
 class MetadataError(Exception):
diff --git a/zarr/hierarchy.py b/zarr/hierarchy.py
index d0ea600010..6200eafcaa 100644
--- a/zarr/hierarchy.py
+++ b/zarr/hierarchy.py
@@ -1,23 +1,22 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import, print_function, division
+from collections.abc import MutableMapping
 from itertools import islice
 
 import numpy as np
 
-
-from zarr.compat import PY2, MutableMapping
 from zarr.attrs import Attributes
 from zarr.core import Array
-from zarr.storage import (contains_array, contains_group, init_group,
-                          MemoryStore, group_meta_key, attrs_key, listdir, rename, rmdir)
-from zarr.creation import (array, create, empty, zeros, ones, full,
-                           empty_like, zeros_like, ones_like, full_like,
-                           normalize_store_arg)
-from zarr.util import (normalize_storage_path, normalize_shape, InfoReporter, TreeViewer,
-                       is_valid_python_name, instance_dir, nolock)
-from zarr.errors import (err_contains_array, err_contains_group, err_group_not_found,
-                         err_read_only)
+from zarr.creation import (array, create, empty, empty_like, full, full_like,
+                           normalize_store_arg, ones, ones_like, zeros,
+                           zeros_like)
+from zarr.errors import (err_contains_array, err_contains_group,
+                         err_group_not_found, err_read_only)
 from zarr.meta import decode_group_metadata
+from zarr.storage import (MemoryStore, attrs_key, contains_array,
+                          contains_group, group_meta_key, init_group, listdir,
+                          rename, rmdir)
+from zarr.util import (InfoReporter, TreeViewer, is_valid_python_name, nolock,
+                       normalize_shape, normalize_storage_path)
 
 
 class Group(MutableMapping):
@@ -218,7 +217,7 @@ def __len__(self):
 
     def __repr__(self):
         t = type(self)
-        r = '<%s.%s' % (t.__module__, t.__name__)
+        r = '<{}.{}'.format(t.__module__, t.__name__)
         if self.name:
             r += ' %r' % self.name
         if self._read_only:
@@ -229,7 +228,7 @@ def __repr__(self):
     def info_items(self):
 
         def typestr(o):
-            return '%s.%s' % (type(o).__module__, type(o).__name__)
+            return '{}.{}'.format(type(o).__module__, type(o).__name__)
 
         items = []
 
@@ -353,11 +352,8 @@ def __getattr__(self, item):
             raise AttributeError
 
     def __dir__(self):
-        if PY2:  # pragma: py3 no cover
-            base = instance_dir(self)
-        else:  # pragma: py2 no cover
-            # noinspection PyUnresolvedReferences
-            base = super().__dir__()
+        # noinspection PyUnresolvedReferences
+        base = super().__dir__()
         keys = sorted(set(base + list(self)))
         keys = [k for k in keys if is_valid_python_name(k)]
         return keys
diff --git a/zarr/indexing.py b/zarr/indexing.py
index 988489e0bb..ff4595d124 100644
--- a/zarr/indexing.py
+++ b/zarr/indexing.py
@@ -1,15 +1,12 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import, print_function, division
-import numbers
-import itertools
 import collections
-
+import itertools
+import numbers
 
 import numpy as np
 
-
-from zarr.errors import (err_too_many_indices, err_boundscheck, err_negative_step,
-                         err_vindex_invalid_selection)
+from zarr.errors import (err_boundscheck, err_negative_step,
+                         err_too_many_indices, err_vindex_invalid_selection)
 
 
 def is_integer(x):
diff --git a/zarr/meta.py b/zarr/meta.py
index 8b5012c612..181c6efa69 100644
--- a/zarr/meta.py
+++ b/zarr/meta.py
@@ -1,16 +1,12 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import, print_function, division
 import base64
-
+from collections.abc import Mapping
 
 import numpy as np
 
-
-from zarr.compat import PY2, Mapping
 from zarr.errors import MetadataError
 from zarr.util import json_dumps, json_loads
 
-
 ZARR_FORMAT = 2
 
 
@@ -89,11 +85,7 @@ def _decode_dtype_descr(d):
     # need to convert list of lists to list of tuples
     if isinstance(d, list):
         # recurse to handle nested structures
-        if PY2:  # pragma: py3 no cover
-            # under PY2 numpy rejects unicode field names
-            d = [(k[0].encode("ascii"), _decode_dtype_descr(k[1])) + tuple(k[2:]) for k in d]
-        else:  # pragma: py2 no cover
-            d = [(k[0], _decode_dtype_descr(k[1])) + tuple(k[2:]) for k in d]
+        d = [(k[0], _decode_dtype_descr(k[1])) + tuple(k[2:]) for k in d]
     return d
 
 
@@ -191,9 +183,7 @@ def encode_fill_value(v, dtype):
              encode_fill_value(v.imag, dtype.type().imag.dtype))
         return v
     elif dtype.kind in 'SV':
-        v = base64.standard_b64encode(v)
-        if not PY2:  # pragma: py2 no cover
-            v = str(v, 'ascii')
+        v = str(base64.standard_b64encode(v), 'ascii')
         return v
     elif dtype.kind == 'U':
         return v
diff --git a/zarr/meta_v1.py b/zarr/meta_v1.py
index 50474359cd..9f40e84397 100644
--- a/zarr/meta_v1.py
+++ b/zarr/meta_v1.py
@@ -1,17 +1,13 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import, print_function, division
 import json
 
-
 import numpy as np
 
-
-from zarr.compat import PY2, text_type
 from zarr.errors import MetadataError
 
 
 def decode_metadata(b):
-    s = text_type(b, 'ascii')
+    s = str(b, 'ascii')
     meta = json.loads(s)
     zarr_format = meta.get('zarr_format', None)
     if zarr_format != 1:
@@ -60,12 +56,7 @@ def _decode_dtype_descr(d):
     # need to convert list of lists to list of tuples
     if isinstance(d, list):
         # recurse to handle nested structures
-        if PY2:
-            # under PY2 numpy rejects unicode field names
-            d = [(f.encode('ascii'), _decode_dtype_descr(v))
-                 for f, v in d]
-        else:
-            d = [(f, _decode_dtype_descr(v)) for f, v in d]
+        d = [(f, _decode_dtype_descr(v)) for f, v in d]
     return d
 
 
diff --git a/zarr/n5.py b/zarr/n5.py
index 34018098ed..df44409565 100644
--- a/zarr/n5.py
+++ b/zarr/n5.py
@@ -1,23 +1,21 @@
 # -*- coding: utf-8 -*-
 """This module contains a storage class and codec to support the N5 format.
 """
-from __future__ import absolute_import, division
-from .meta import ZARR_FORMAT, json_dumps, json_loads
-from .storage import (
-        NestedDirectoryStore,
-        group_meta_key as zarr_group_meta_key,
-        array_meta_key as zarr_array_meta_key,
-        attrs_key as zarr_attrs_key,
-        _prog_ckey, _prog_number)
-from numcodecs.abc import Codec
-from numcodecs.compat import ndarray_copy
-from numcodecs.registry import register_codec, get_codec
-import numpy as np
+import os
 import struct
 import sys
-import os
 import warnings
 
+import numpy as np
+from numcodecs.abc import Codec
+from numcodecs.compat import ndarray_copy
+from numcodecs.registry import get_codec, register_codec
+
+from .meta import ZARR_FORMAT, json_dumps, json_loads
+from .storage import NestedDirectoryStore, _prog_ckey, _prog_number
+from .storage import array_meta_key as zarr_array_meta_key
+from .storage import attrs_key as zarr_attrs_key
+from .storage import group_meta_key as zarr_group_meta_key
 
 zarr_to_n5_keys = [
     ('chunks', 'blockSize'),
@@ -571,7 +569,7 @@ def decode(self, chunk, out=None):
 
             # out should only be used if we read a complete chunk
             assert chunk_shape == self.chunk_shape, (
-                "Expected chunk of shape %s, found %s" % (
+                "Expected chunk of shape {}, found {}".format(
                     self.chunk_shape,
                     chunk_shape))
 
diff --git a/zarr/storage.py b/zarr/storage.py
index 03ebdefeac..4f4e9c7a09 100644
--- a/zarr/storage.py
+++ b/zarr/storage.py
@@ -15,34 +15,34 @@
 path) and a `getsize` method (return the size in bytes of a given value).
 
 """
-from __future__ import absolute_import, print_function, division
-from collections import OrderedDict
-import os
-import operator
-import tempfile
-import zipfile
-import shutil
 import atexit
 import errno
+import glob
+import multiprocessing
+import operator
+import os
 import re
+import shutil
 import sys
-import multiprocessing
+import tempfile
+import warnings
+import zipfile
+from collections import OrderedDict
+from collections.abc import MutableMapping
+from os import scandir
 from pickle import PicklingError
 from threading import Lock, RLock
-import glob
-import warnings
-
 
-from zarr.util import (json_loads, normalize_shape, normalize_chunks, normalize_order,
-                       normalize_storage_path, buffer_size,
-                       normalize_fill_value, nolock, normalize_dtype)
-from zarr.meta import encode_array_metadata, encode_group_metadata
-from zarr.compat import PY2, MutableMapping, OrderedDict_move_to_end, scandir
-from numcodecs.registry import codec_registry
 from numcodecs.compat import ensure_bytes, ensure_contiguous_ndarray
-from zarr.errors import (err_contains_group, err_contains_array, err_bad_compressor,
-                         err_fspath_exists_notdir, err_read_only, MetadataError)
+from numcodecs.registry import codec_registry
 
+from zarr.errors import (MetadataError, err_bad_compressor, err_contains_array,
+                         err_contains_group, err_fspath_exists_notdir,
+                         err_read_only)
+from zarr.meta import encode_array_metadata, encode_group_metadata
+from zarr.util import (buffer_size, json_loads, nolock, normalize_chunks,
+                       normalize_dtype, normalize_fill_value, normalize_order,
+                       normalize_shape, normalize_storage_path)
 
 __doctest_requires__ = {
     ('RedisStore', 'RedisStore.*'): ['redis'],
@@ -1420,12 +1420,8 @@ class DBMStore(MutableMapping):
     def __init__(self, path, flag='c', mode=0o666, open=None, write_lock=True,
                  **open_kwargs):
         if open is None:
-            if PY2:  # pragma: py3 no cover
-                import anydbm
-                open = anydbm.open
-            else:  # pragma: py2 no cover
-                import dbm
-                open = dbm.open
+            import dbm
+            open = dbm.open
         path = os.path.abspath(path)
         # noinspection PyArgumentList
         self.db = open(path, flag, mode, **open_kwargs)
@@ -1444,7 +1440,7 @@ def __init__(self, path, flag='c', mode=0o666, open=None, write_lock=True,
 
     def __getstate__(self):
         try:
-            self.flush()  # needed for py2 and ndbm
+            self.flush()  # needed for ndbm
         except Exception:
             # flush may fail if db has already been closed
             pass
@@ -1523,24 +1519,14 @@ def __contains__(self, key):
         return key in self.db
 
 
-if PY2:  # pragma: py3 no cover
-
-    def _lmdb_decode_key_buffer(key):
-        # assume buffers=True
-        return str(key)
-
-    def _lmdb_decode_key_bytes(key):
-        return key
-
-else:  # pragma: py2 no cover
+def _lmdb_decode_key_buffer(key):
+    # assume buffers=True
+    return key.tobytes().decode('ascii')
 
-    def _lmdb_decode_key_buffer(key):
-        # assume buffers=True
-        return key.tobytes().decode('ascii')
 
-    def _lmdb_decode_key_bytes(key):
-        # assume buffers=False
-        return key.decode('ascii')
+def _lmdb_decode_key_bytes(key):
+    # assume buffers=False
+    return key.decode('ascii')
 
 
 class LMDBStore(MutableMapping):
@@ -1871,7 +1857,7 @@ def __getitem__(self, key):
                 # cache hit if no KeyError is raised
                 self.hits += 1
                 # treat the end as most recently used
-                OrderedDict_move_to_end(self._values_cache, key)
+                self._values_cache.move_to_end(key)
 
         except KeyError:
             # cache miss, retrieve value from the store
@@ -2187,14 +2173,7 @@ def update(self, *args, **kwargs):
         kv_list = []
         for dct in args:
             for k, v in dct.items():
-                # Python 2 cannot store `memoryview`s, but it can store
-                # `buffer`s. However Python 2 won't return `bytes` then. So we
-                # coerce to `bytes`, which are handled correctly. Python 3
-                # doesn't have these issues.
-                if PY2:  # pragma: py3 no cover
-                    v = ensure_bytes(v)
-                else:  # pragma: py2 no cover
-                    v = ensure_contiguous_ndarray(v)
+                v = ensure_contiguous_ndarray(v)
 
                 # Accumulate key-value pairs for storage
                 kv_list.append((k, v))
diff --git a/zarr/sync.py b/zarr/sync.py
index fe936e13e2..1498678fb4 100644
--- a/zarr/sync.py
+++ b/zarr/sync.py
@@ -1,9 +1,7 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import, print_function, division
-from threading import Lock
-from collections import defaultdict
 import os
-
+from collections import defaultdict
+from threading import Lock
 
 import fasteners
 
diff --git a/zarr/tests/__init__.py b/zarr/tests/__init__.py
index 1ee762b218..40a96afc6f 100644
--- a/zarr/tests/__init__.py
+++ b/zarr/tests/__init__.py
@@ -1,2 +1 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import, print_function, division
diff --git a/zarr/tests/test_attrs.py b/zarr/tests/test_attrs.py
index f546224c73..5ad39ef1a9 100644
--- a/zarr/tests/test_attrs.py
+++ b/zarr/tests/test_attrs.py
@@ -1,15 +1,10 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import, print_function, division
 import json
 import unittest
 
-
 import pytest
 
-
 from zarr.attrs import Attributes
-from zarr.compat import binary_type, text_type
-from zarr.errors import PermissionError
 from zarr.tests.util import CountingDict
 
 
@@ -29,8 +24,8 @@ def test_storage(self):
         a['foo'] = 'bar'
         a['baz'] = 42
         assert 'attrs' in store
-        assert isinstance(store['attrs'], binary_type)
-        d = json.loads(text_type(store['attrs'], 'ascii'))
+        assert isinstance(store['attrs'], bytes)
+        d = json.loads(str(store['attrs'], 'ascii'))
         assert dict(foo='bar', baz=42) == d
 
     def test_get_set_del_contains(self):
diff --git a/zarr/tests/test_convenience.py b/zarr/tests/test_convenience.py
index d33d23ecb8..3833c67d17 100644
--- a/zarr/tests/test_convenience.py
+++ b/zarr/tests/test_convenience.py
@@ -1,24 +1,22 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import, print_function, division
-import tempfile
 import atexit
 import os
+import tempfile
 import unittest
 from numbers import Integral
 
-
 import numpy as np
-from numpy.testing import assert_array_equal
-from numcodecs import Zlib, Adler32
 import pytest
+from numcodecs import Adler32, Zlib
+from numpy.testing import assert_array_equal
 
-
-from zarr.convenience import (open, save, save_group, load, copy_store, copy,
-                              consolidate_metadata, open_consolidated)
-from zarr.storage import atexit_rmtree, MemoryStore, getsize, ConsolidatedMetadataStore
+from zarr.convenience import (consolidate_metadata, copy, copy_store, load,
+                              open, open_consolidated, save, save_group)
 from zarr.core import Array
+from zarr.errors import CopyError
 from zarr.hierarchy import Group, group
-from zarr.errors import CopyError, PermissionError
+from zarr.storage import (ConsolidatedMetadataStore, MemoryStore,
+                          atexit_rmtree, getsize)
 
 
 def test_open_array():
diff --git a/zarr/tests/test_core.py b/zarr/tests/test_core.py
index 43daca9f03..00bf04f0ab 100644
--- a/zarr/tests/test_core.py
+++ b/zarr/tests/test_core.py
@@ -1,17 +1,28 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import, print_function, division
-import unittest
-from tempfile import mkdtemp, mktemp
 import atexit
-import shutil
-import pickle
 import os
-import warnings
-
+import pickle
+import shutil
+import unittest
+from itertools import zip_longest
+from tempfile import mkdtemp, mktemp
 
 import numpy as np
-from numpy.testing import assert_array_equal, assert_array_almost_equal
 import pytest
+from numcodecs import (BZ2, JSON, LZ4, Blosc, Categorize, Delta,
+                       FixedScaleOffset, GZip, MsgPack, Pickle, VLenArray,
+                       VLenBytes, VLenUTF8, Zlib)
+from numcodecs.compat import ensure_bytes, ensure_ndarray
+from numcodecs.tests.common import greetings
+from numpy.testing import assert_array_almost_equal, assert_array_equal
+
+from zarr.core import Array
+from zarr.meta import json_loads
+from zarr.n5 import N5Store, n5_keywords
+from zarr.storage import (ABSStore, DBMStore, DirectoryStore, LMDBStore,
+                          LRUStoreCache, NestedDirectoryStore, SQLiteStore,
+                          atexit_rmglob, atexit_rmtree, init_array, init_group)
+from zarr.util import buffer_size
 
 try:
     import azure.storage.blob as asb
@@ -19,32 +30,11 @@
     asb = None
 
 
-from zarr.storage import (DirectoryStore, init_array, init_group, NestedDirectoryStore,
-                          DBMStore, LMDBStore, SQLiteStore, ABSStore, atexit_rmtree,
-                          atexit_rmglob, LRUStoreCache)
-from zarr.core import Array
-from zarr.errors import PermissionError
-from zarr.compat import PY2, text_type, binary_type, zip_longest
-from zarr.meta import json_loads
-from zarr.util import buffer_size
-from zarr.n5 import n5_keywords, N5Store
-from numcodecs import (Delta, FixedScaleOffset, LZ4, GZip, Zlib, Blosc, BZ2, MsgPack, Pickle,
-                       Categorize, JSON, VLenUTF8, VLenBytes, VLenArray)
-from numcodecs.compat import ensure_bytes, ensure_ndarray
-from numcodecs.tests.common import greetings
-
-
 # also check for environment variables indicating whether tests requiring
 # services should be run
 ZARR_TEST_ABS = os.environ.get('ZARR_TEST_ABS', '0')
 
 
-# needed for PY2/PY3 consistent behaviour
-if PY2:  # pragma: py3 no cover
-    warnings.resetwarnings()
-    warnings.simplefilter('always')
-
-
 # noinspection PyMethodMayBeStatic
 class TestArray(unittest.TestCase):
 
@@ -102,10 +92,7 @@ def test_store_has_text_keys(self):
         z = self.create_array(shape=(1050,), chunks=100, dtype='f8', compressor=[])
         z[:] = np.random.random(z.shape)
 
-        if PY2:  # pragma: py3 no cover
-            expected_type = (str, text_type)
-        else:    # pragma: py2 no cover
-            expected_type = text_type
+        expected_type = str
 
         for k in z.chunk_store.keys():
             if not isinstance(k, expected_type):  # pragma: no cover
@@ -134,7 +121,7 @@ def test_store_has_bytes_values(self):
         z[:] = np.random.random(z.shape)
 
         # Check in-memory array only contains `bytes`
-        assert all([isinstance(v, binary_type) for v in z.chunk_store.values()])
+        assert all([isinstance(v, bytes) for v in z.chunk_store.values()])
 
     def test_nbytes_stored(self):
 
@@ -1102,7 +1089,7 @@ def test_object_arrays_vlen_text(self):
         assert_array_equal(data, a)
 
         # convenience API
-        z = self.create_array(shape=data.shape, dtype=text_type)
+        z = self.create_array(shape=data.shape, dtype=str)
         assert z.dtype == object
         assert isinstance(z.filters[0], VLenUTF8)
         z[:] = data
@@ -1143,7 +1130,7 @@ def test_object_arrays_vlen_bytes(self):
         assert_array_equal(data, a)
 
         # convenience API
-        z = self.create_array(shape=data.shape, dtype=binary_type)
+        z = self.create_array(shape=data.shape, dtype=bytes)
         assert z.dtype == object
         assert isinstance(z.filters[0], VLenBytes)
         z[:] = data
@@ -1640,7 +1627,7 @@ def test_object_arrays_vlen_text(self):
 
         # convenience API
         with pytest.raises(ValueError):
-            self.create_array(shape=data.shape, dtype=text_type)
+            self.create_array(shape=data.shape, dtype=str)
 
     def test_object_arrays_vlen_bytes(self):
 
@@ -1652,7 +1639,7 @@ def test_object_arrays_vlen_bytes(self):
 
         # convenience API
         with pytest.raises(ValueError):
-            self.create_array(shape=data.shape, dtype=binary_type)
+            self.create_array(shape=data.shape, dtype=bytes)
 
     def test_object_arrays_vlen_array(self):
 
diff --git a/zarr/tests/test_creation.py b/zarr/tests/test_creation.py
index 65a0caff63..d28ef401b6 100644
--- a/zarr/tests/test_creation.py
+++ b/zarr/tests/test_creation.py
@@ -1,26 +1,22 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import, print_function, division
-import tempfile
-import shutil
 import atexit
 import os.path
-
+import shutil
+import tempfile
 
 import numpy as np
-from numpy.testing import assert_array_equal
 import pytest
+from numpy.testing import assert_array_equal
 
-
-from zarr.creation import (array, empty, zeros, ones, full, open_array, empty_like,
-                           zeros_like, ones_like, full_like, open_like, create)
-from zarr.sync import ThreadSynchronizer
+from zarr.codecs import Zlib
 from zarr.core import Array
-from zarr.storage import DirectoryStore
-from zarr.n5 import N5Store
+from zarr.creation import (array, create, empty, empty_like, full, full_like,
+                           ones, ones_like, open_array, open_like, zeros,
+                           zeros_like)
 from zarr.hierarchy import open_group
-from zarr.errors import PermissionError
-from zarr.codecs import Zlib
-from zarr.compat import PY2
+from zarr.n5 import N5Store
+from zarr.storage import DirectoryStore
+from zarr.sync import ThreadSynchronizer
 
 
 # something bcolz-like
@@ -162,17 +158,8 @@ def test_full():
 
     # bytes fill value / unicode dtype
     v = b'xxx'
-    if PY2:  # pragma: py3 no cover
-        # allow this on PY2
-        z = full(100, chunks=10, fill_value=v, dtype='U3')
-        a = z[...]
-        assert z.dtype == a.dtype
-        assert v == a[0]
-        assert np.all(a == v)
-    else:  # pragma: py2 no cover
-        # be strict on PY3
-        with pytest.raises(ValueError):
-            full(100, chunks=10, fill_value=v, dtype='U3')
+    with pytest.raises(ValueError):
+        full(100, chunks=10, fill_value=v, dtype='U3')
 
 
 def test_open_array():
@@ -476,15 +463,12 @@ def test_compression_args():
     assert 'zlib' == z.compressor.codec_id
     assert 9 == z.compressor.level
 
-    # cannot get warning tests to work on PY2
-    if not PY2:  # pragma: py2 no cover
-
-        with pytest.warns(UserWarning):
-            # 'compressor' overrides 'compression'
-            create(100, compressor=Zlib(9), compression='bz2', compression_opts=1)
-        with pytest.warns(UserWarning):
-            # 'compressor' ignores 'compression_opts'
-            create(100, compressor=Zlib(9), compression_opts=1)
+    with pytest.warns(UserWarning):
+        # 'compressor' overrides 'compression'
+        create(100, compressor=Zlib(9), compression='bz2', compression_opts=1)
+    with pytest.warns(UserWarning):
+        # 'compressor' ignores 'compression_opts'
+        create(100, compressor=Zlib(9), compression_opts=1)
 
 
 def test_create_read_only():
diff --git a/zarr/tests/test_filters.py b/zarr/tests/test_filters.py
index 4ac256a438..7abe6d960a 100644
--- a/zarr/tests/test_filters.py
+++ b/zarr/tests/test_filters.py
@@ -1,16 +1,11 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import, print_function, division
-
-
 import numpy as np
-from numpy.testing import assert_array_equal, assert_array_almost_equal
+from numcodecs import (BZ2, AsType, Blosc, Categorize, Delta, FixedScaleOffset,
+                       PackBits, Quantize, Zlib)
+from numpy.testing import assert_array_almost_equal, assert_array_equal
 
-
-from numcodecs import (AsType, Delta, FixedScaleOffset, PackBits, Categorize, Zlib, Blosc,
-                       BZ2, Quantize)
 from zarr.creation import array
 
-
 compressors = [
     None,
     Zlib(),
diff --git a/zarr/tests/test_hierarchy.py b/zarr/tests/test_hierarchy.py
index 546e2ab93f..6e2292ab4c 100644
--- a/zarr/tests/test_hierarchy.py
+++ b/zarr/tests/test_hierarchy.py
@@ -1,18 +1,27 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import, print_function, division
-import unittest
-import tempfile
 import atexit
-import shutil
-import textwrap
 import os
 import pickle
-import warnings
-
+import shutil
+import tempfile
+import textwrap
+import unittest
 
 import numpy as np
-from numpy.testing import assert_array_equal
 import pytest
+from numcodecs import Zlib
+from numpy.testing import assert_array_equal
+
+from zarr.attrs import Attributes
+from zarr.core import Array
+from zarr.creation import open_array
+from zarr.hierarchy import Group, group, open_group
+from zarr.storage import (ABSStore, DBMStore, DirectoryStore, LMDBStore,
+                          LRUStoreCache, MemoryStore, NestedDirectoryStore,
+                          SQLiteStore, ZipStore, array_meta_key, atexit_rmglob,
+                          atexit_rmtree, group_meta_key, init_array,
+                          init_group)
+from zarr.util import InfoReporter
 
 try:
     import azure.storage.blob as asb
@@ -20,31 +29,11 @@
     asb = None
 
 
-from zarr.storage import (MemoryStore, DirectoryStore, ZipStore, init_group, init_array,
-                          array_meta_key, group_meta_key, atexit_rmtree,
-                          NestedDirectoryStore, DBMStore, LMDBStore, SQLiteStore,
-                          ABSStore, atexit_rmglob, LRUStoreCache)
-from zarr.core import Array
-from zarr.compat import PY2, text_type
-from zarr.hierarchy import Group, group, open_group
-from zarr.attrs import Attributes
-from zarr.errors import PermissionError
-from zarr.creation import open_array
-from zarr.util import InfoReporter
-from numcodecs import Zlib
-
-
 # also check for environment variables indicating whether tests requiring
 # services should be run
 ZARR_TEST_ABS = os.environ.get('ZARR_TEST_ABS', '0')
 
 
-# needed for PY2/PY3 consistent behaviour
-if PY2:  # pragma: py3 no cover
-    warnings.resetwarnings()
-    warnings.simplefilter('always')
-
-
 # noinspection PyStatementEffect
 class TestGroup(unittest.TestCase):
 
@@ -1191,10 +1180,8 @@ def test_group_key_completions():
 
 def _check_tree(g, expect_bytes, expect_text):
     assert expect_bytes == bytes(g.tree())
-    assert expect_text == text_type(g.tree())
+    assert expect_text == str(g.tree())
     expect_repr = expect_text
-    if PY2:  # pragma: py3 no cover
-        expect_repr = expect_bytes
     assert expect_repr == repr(g.tree())
     # test _repr_html_ lightly
     # noinspection PyProtectedMember
diff --git a/zarr/tests/test_indexing.py b/zarr/tests/test_indexing.py
index 8aeeab51b9..a68223a5f0 100644
--- a/zarr/tests/test_indexing.py
+++ b/zarr/tests/test_indexing.py
@@ -1,15 +1,11 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import, print_function, division
-
-
 import numpy as np
-from numpy.testing import assert_array_equal
 import pytest
+from numpy.testing import assert_array_equal
 
-
-from zarr.indexing import (normalize_integer_selection, replace_ellipsis, oindex,
-                           oindex_set)
 import zarr
+from zarr.indexing import (normalize_integer_selection, oindex, oindex_set,
+                           replace_ellipsis)
 
 
 def test_normalize_integer_selection():
diff --git a/zarr/tests/test_info.py b/zarr/tests/test_info.py
index e0d2330d6b..1488f59275 100644
--- a/zarr/tests/test_info.py
+++ b/zarr/tests/test_info.py
@@ -1,9 +1,7 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import, print_function, division
-
+import numcodecs
 
 import zarr
-import numcodecs
 
 
 def test_info():
diff --git a/zarr/tests/test_meta.py b/zarr/tests/test_meta.py
index 7ade1b95c2..5051ff4379 100644
--- a/zarr/tests/test_meta.py
+++ b/zarr/tests/test_meta.py
@@ -1,25 +1,22 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import, print_function, division
-import json
 import base64
-
+import json
 
 import numpy as np
 import pytest
 
-
-from zarr.compat import binary_type, text_type, PY2
-from zarr.meta import (decode_array_metadata, encode_dtype, decode_dtype, ZARR_FORMAT,
-                       decode_group_metadata, encode_array_metadata)
+from zarr.codecs import Blosc, Delta, Zlib
 from zarr.errors import MetadataError
-from zarr.codecs import Delta, Zlib, Blosc
+from zarr.meta import (ZARR_FORMAT, decode_array_metadata, decode_dtype,
+                       decode_group_metadata, encode_array_metadata,
+                       encode_dtype)
 
 
 def assert_json_equal(expect, actual):
-    if isinstance(expect, binary_type):  # pragma: py3 no cover
-        expect = text_type(expect, 'ascii')
-    if isinstance(actual, binary_type):
-        actual = text_type(actual, 'ascii')
+    if isinstance(expect, bytes):  # pragma: py3 no cover
+        expect = str(expect, 'ascii')
+    if isinstance(actual, bytes):
+        actual = str(actual, 'ascii')
     ej = json.loads(expect)
     aj = json.loads(actual)
     assert ej == aj
@@ -368,8 +365,7 @@ def test_encode_decode_fill_values_bytes():
 
         # define expected metadata encoded as JSON
         s = base64.standard_b64encode(v)
-        if not PY2:
-            s = s.decode()
+        s = s.decode()
         meta_json = '''{
             "chunks": [10],
             "compressor": {"id": "zlib", "level": 1},
diff --git a/zarr/tests/test_storage.py b/zarr/tests/test_storage.py
index a713acaf8a..0b517c4399 100644
--- a/zarr/tests/test_storage.py
+++ b/zarr/tests/test_storage.py
@@ -1,20 +1,34 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import, print_function, division
-from contextlib import contextmanager
-import unittest
-import tempfile
+import array
 import atexit
-import pickle
 import json
-import array
-import shutil
 import os
+import pickle
+import shutil
+import tempfile
+import unittest
+from contextlib import contextmanager
 from pickle import PicklingError
 
-
 import numpy as np
-from numpy.testing import assert_array_equal, assert_array_almost_equal
 import pytest
+from numpy.testing import assert_array_almost_equal, assert_array_equal
+
+from zarr.codecs import BZ2, AsType, Blosc, Zlib
+from zarr.errors import MetadataError
+from zarr.hierarchy import group
+from zarr.meta import (ZARR_FORMAT, decode_array_metadata,
+                       decode_group_metadata, encode_array_metadata,
+                       encode_group_metadata)
+from zarr.n5 import N5Store
+from zarr.storage import (ABSStore, ConsolidatedMetadataStore, DBMStore,
+                          DictStore, DirectoryStore, LMDBStore, LRUStoreCache,
+                          MemoryStore, MongoDBStore, NestedDirectoryStore,
+                          RedisStore, SQLiteStore, TempStore, ZipStore,
+                          array_meta_key, atexit_rmglob, atexit_rmtree,
+                          attrs_key, default_compressor, getsize,
+                          group_meta_key, init_array, init_group, migrate_1to2)
+from zarr.tests.util import CountingDict
 
 try:
     import sqlite3
@@ -36,20 +50,6 @@
 except ImportError:  # pragma: no cover
     redis = None
 
-from zarr.storage import (init_array, array_meta_key, attrs_key, DictStore, MemoryStore,
-                          DirectoryStore, ZipStore, init_group, group_meta_key,
-                          getsize, migrate_1to2, TempStore, atexit_rmtree,
-                          NestedDirectoryStore, default_compressor, DBMStore,
-                          LMDBStore, SQLiteStore, ABSStore, atexit_rmglob, LRUStoreCache,
-                          ConsolidatedMetadataStore, MongoDBStore, RedisStore)
-from zarr.meta import (decode_array_metadata, encode_array_metadata, ZARR_FORMAT,
-                       decode_group_metadata, encode_group_metadata)
-from zarr.compat import PY2
-from zarr.codecs import AsType, Zlib, Blosc, BZ2
-from zarr.errors import PermissionError, MetadataError
-from zarr.hierarchy import group
-from zarr.n5 import N5Store
-from zarr.tests.util import CountingDict
 
 try:
     from zarr.codecs import LZMA
@@ -988,19 +988,14 @@ class TestDBMStoreDumb(TestDBMStore):
     def create_store(self):
         path = tempfile.mktemp(suffix='.dumbdbm')
         atexit.register(atexit_rmglob, path + '*')
-        if PY2:  # pragma: py3 no cover
-            import dumbdbm
-        else:  # pragma: py2 no cover
-            import dbm.dumb as dumbdbm
+
+        import dbm.dumb as dumbdbm
         store = DBMStore(path, flag='n', open=dumbdbm.open)
         return store
 
 
 try:
-    if PY2:  # pragma: py3 no cover
-        import gdbm
-    else:  # pragma: py2 no cover
-        import dbm.gnu as gdbm
+    import dbm.gnu as gdbm
 except ImportError:  # pragma: no cover
     gdbm = None
 
@@ -1015,20 +1010,20 @@ def create_store(self):
         return store
 
 
-if not PY2:  # pragma: py2 no cover
-    try:
-        import dbm.ndbm as ndbm
-    except ImportError:  # pragma: no cover
-        ndbm = None
+try:
+    import dbm.ndbm as ndbm
+except ImportError:  # pragma: no cover
+    ndbm = None
+
 
-    @unittest.skipIf(ndbm is None, reason='ndbm is not installed')
-    class TestDBMStoreNDBM(TestDBMStore):
+@unittest.skipIf(ndbm is None, reason='ndbm is not installed')
+class TestDBMStoreNDBM(TestDBMStore):
 
-        def create_store(self):
-            path = tempfile.mktemp(suffix='.ndbm')
-            atexit.register(atexit_rmglob, path + '*')
-            store = DBMStore(path, flag='n', open=ndbm.open)
-            return store
+    def create_store(self):
+        path = tempfile.mktemp(suffix='.ndbm')
+        atexit.register(atexit_rmglob, path + '*')
+        store = DBMStore(path, flag='n', open=ndbm.open)
+        return store
 
 
 try:
@@ -1059,12 +1054,7 @@ class TestLMDBStore(StoreTests, unittest.TestCase):
     def create_store(self):
         path = tempfile.mktemp(suffix='.lmdb')
         atexit.register(atexit_rmtree, path)
-        if PY2:  # pragma: py3 no cover
-            # don't use buffers, otherwise would have to rewrite tests as bytes and
-            # buffer don't compare equal in PY2
-            buffers = False
-        else:  # pragma: py2 no cover
-            buffers = True
+        buffers = True
         store = LMDBStore(path, buffers=buffers)
         return store
 
diff --git a/zarr/tests/test_sync.py b/zarr/tests/test_sync.py
index 4ee62e68e9..8af28c152d 100644
--- a/zarr/tests/test_sync.py
+++ b/zarr/tests/test_sync.py
@@ -1,26 +1,23 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import, print_function, division
-from tempfile import mkdtemp
 import atexit
 import shutil
-from multiprocessing.pool import ThreadPool
+import tempfile
 from multiprocessing import Pool as ProcessPool
 from multiprocessing import cpu_count
-import tempfile
-
+from multiprocessing.pool import ThreadPool
+from tempfile import mkdtemp
 
 import numpy as np
 from numpy.testing import assert_array_equal
 
-
+from zarr.attrs import Attributes
+from zarr.core import Array
+from zarr.hierarchy import Group
+from zarr.storage import DirectoryStore, atexit_rmtree, init_array, init_group
+from zarr.sync import ProcessSynchronizer, ThreadSynchronizer
 from zarr.tests.test_attrs import TestAttributes
 from zarr.tests.test_core import TestArray
 from zarr.tests.test_hierarchy import TestGroup
-from zarr.sync import ThreadSynchronizer, ProcessSynchronizer
-from zarr.core import Array
-from zarr.attrs import Attributes
-from zarr.storage import init_array, DirectoryStore, init_group, atexit_rmtree
-from zarr.hierarchy import Group
 
 
 class TestAttributesWithThreadSynchronizer(TestAttributes):
diff --git a/zarr/tests/test_util.py b/zarr/tests/test_util.py
index 836b494b46..809ef8a6fa 100644
--- a/zarr/tests/test_util.py
+++ b/zarr/tests/test_util.py
@@ -1,15 +1,11 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import, print_function, division
-
-
 import numpy as np
 import pytest
 
-
-from zarr.util import (normalize_shape, normalize_chunks, is_total_slice,
-                       normalize_resize_args, human_readable_size, normalize_order,
-                       guess_chunks, info_html_report, info_text_report,
-                       normalize_fill_value)
+from zarr.util import (guess_chunks, human_readable_size, info_html_report,
+                       info_text_report, is_total_slice, normalize_chunks,
+                       normalize_fill_value, normalize_order,
+                       normalize_resize_args, normalize_shape)
 
 
 def test_normalize_shape():
diff --git a/zarr/tests/util.py b/zarr/tests/util.py
index b86e1a94c3..2b6a809d8b 100644
--- a/zarr/tests/util.py
+++ b/zarr/tests/util.py
@@ -1,7 +1,6 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import, print_function, division
 import collections
-from zarr.compat import MutableMapping
+from collections.abc import MutableMapping
 
 
 class CountingDict(MutableMapping):
diff --git a/zarr/util.py b/zarr/util.py
index 6447445c00..cc0ef1e729 100644
--- a/zarr/util.py
+++ b/zarr/util.py
@@ -1,33 +1,27 @@
 # -*- coding: utf-8 -*-
-from __future__ import absolute_import, print_function, division
-from textwrap import TextWrapper, dedent
 import codecs
+import inspect
 import json
 import numbers
 import uuid
-import inspect
-
+from textwrap import TextWrapper, dedent
 
+import numpy as np
 from asciitree import BoxStyle, LeftAligned
 from asciitree.traversal import Traversal
-import numpy as np
-from numcodecs.compat import ensure_ndarray, ensure_contiguous_ndarray
+from numcodecs.compat import ensure_contiguous_ndarray, ensure_ndarray
 from numcodecs.registry import codec_registry
 
-
-from zarr.compat import PY2, text_type, binary_type
-
-
 # codecs to use for object dtype convenience API
 object_codecs = {
-    text_type.__name__: 'vlen-utf8',
-    binary_type.__name__: 'vlen-bytes',
+    str.__name__: 'vlen-utf8',
+    bytes.__name__: 'vlen-bytes',
     'array': 'vlen-array',
 }
 
 
-def ensure_text_type(s):
-    if not isinstance(s, text_type):
+def ensure_str(s):
+    if not isinstance(s, str):
         s = ensure_contiguous_ndarray(s)
         s = codecs.decode(s, 'ascii')
     return s
@@ -41,7 +35,7 @@ def json_dumps(o):
 
 def json_loads(s):
     """Read JSON in a consistent way."""
-    return json.loads(ensure_text_type(s))
+    return json.loads(ensure_str(s))
 
 
 def normalize_shape(shape):
@@ -265,17 +259,13 @@ def normalize_fill_value(fill_value, dtype):
         # special case unicode because of encoding issues on Windows if passed through numpy
         # https://github.com/alimanfoo/zarr/pull/172#issuecomment-343782713
 
-        if PY2 and isinstance(fill_value, binary_type):  # pragma: py3 no cover
-            # this is OK on PY2, can be written as JSON
-            pass
-
-        elif not isinstance(fill_value, text_type):
+        if not isinstance(fill_value, str):
             raise ValueError('fill_value {!r} is not valid for dtype {}; must be a '
                              'unicode string'.format(fill_value, dtype))
 
     else:
         try:
-            if isinstance(fill_value, binary_type) and dtype.kind == 'V':
+            if isinstance(fill_value, bytes) and dtype.kind == 'V':
                 # special case for numpy 1.14 compatibility
                 fill_value = np.array(fill_value, dtype=dtype.str).view(dtype)[()]
             else:
@@ -292,7 +282,7 @@ def normalize_fill_value(fill_value, dtype):
 def normalize_storage_path(path):
 
     # handle bytes
-    if not PY2 and isinstance(path, bytes):  # pragma: py2 no cover
+    if isinstance(path, bytes):
         path = str(path, 'ascii')
 
     # ensure str
@@ -533,8 +523,7 @@ def __bytes__(self):
 
         # Unicode characters slip in on Python 3.
         # So we need to straighten that out first.
-        if not PY2:
-            result = result.encode()
+        result = result.encode()
 
         return result
 
@@ -547,10 +536,7 @@ def __unicode__(self):
         return drawer(root)
 
     def __repr__(self):
-        if PY2:  # pragma: py3 no cover
-            return self.__bytes__()
-        else:  # pragma: py2 no cover
-            return self.__unicode__()
+        return self.__unicode__()
 
     def _repr_html_(self):
         return tree_html(self.group, expand=self.expand, level=self.level)
@@ -566,28 +552,8 @@ def check_array_shape(param, array, shape):
 
 
 def is_valid_python_name(name):
-    if PY2:  # pragma: py3 no cover
-        import ast
-        # noinspection PyBroadException
-        try:
-            ast.parse('"".{};'.format(name))
-        except Exception:
-            return False
-        else:
-            return True
-    else:  # pragma: py2 no cover
-        from keyword import iskeyword
-        return name.isidentifier() and not iskeyword(name)
-
-
-def instance_dir(obj):  # pragma: py3 no cover
-    """Vanilla implementation of built-in dir() for PY2 to help with overriding __dir__.
-    Based on implementation of dir() in pypy."""
-    d = dict()
-    d.update(obj.__dict__)
-    d.update(class_dir(obj.__class__))
-    result = sorted(d.keys())
-    return result
+    from keyword import iskeyword
+    return name.isidentifier() and not iskeyword(name)
 
 
 def class_dir(klass):  # pragma: py3 no cover