diff --git a/fire/completion.py b/fire/completion.py
index 4393880d..3aa8ab11 100644
--- a/fire/completion.py
+++ b/fire/completion.py
@@ -23,7 +23,6 @@
 import inspect
 
 from fire import inspectutils
-import six
 
 
 def Script(name, component, default_options=None, shell='bash'):
@@ -308,7 +307,7 @@ def MemberVisible(component, name, member, class_attrs=None, verbose=False):
   Returns
     A boolean value indicating whether the member should be included.
   """
-  if isinstance(name, six.string_types) and name.startswith('__'):
+  if isinstance(name, str) and name.startswith('__'):
     return False
   if verbose:
     return True
@@ -316,10 +315,11 @@ def MemberVisible(component, name, member, class_attrs=None, verbose=False):
       or member is division
       or member is print_function):
     return False
-  if isinstance(member, type(absolute_import)) and six.PY34:
+  if isinstance(member, type(absolute_import)):
     return False
-  if inspect.ismodule(member) and member is six:
-    # TODO(dbieber): Determine more generally which modules to hide.
+  # TODO(dbieber): Determine more generally which modules to hide.
+  modules_to_hide = []
+  if inspect.ismodule(member) and member in modules_to_hide:
     return False
   if inspect.isclass(component):
     # If class_attrs has not been provided, compute it.
@@ -336,14 +336,7 @@ def MemberVisible(component, name, member, class_attrs=None, verbose=False):
       tuplegetter = getattr(collections, '_tuplegetter', type(None))
       if isinstance(class_attr.object, tuplegetter):
         return False
-  if (six.PY2 and inspect.isfunction(component)
-      and name in ('func_closure', 'func_code', 'func_defaults',
-                   'func_dict', 'func_doc', 'func_globals', 'func_name')):
-    return False
-  if (six.PY2 and inspect.ismethod(component)
-      and name in ('im_class', 'im_func', 'im_self')):
-    return False
-  if isinstance(name, six.string_types):
+  if isinstance(name, str):
     return not name.startswith('_')
   return True  # Default to including the member
 
@@ -438,7 +431,7 @@ def _FormatForCommand(token):
   Returns:
     The transformed token.
   """
-  if not isinstance(token, six.string_types):
+  if not isinstance(token, str):
     token = str(token)
 
   if token.startswith('_'):
diff --git a/fire/core.py b/fire/core.py
index 0a6dae7d..c61a8b57 100644
--- a/fire/core.py
+++ b/fire/core.py
@@ -67,10 +67,8 @@ def main(argv):
 from fire import trace
 from fire import value_types
 from fire.console import console_io
-import six
 
-if six.PY34:
-  import asyncio  # pylint: disable=import-error,g-import-not-at-top  # pytype: disable=import-error
+import asyncio  # pylint: disable=import-error,g-import-not-at-top  # pytype: disable=import-error
 
 
 def Fire(component=None, command=None, name=None, serialize=None):
@@ -109,7 +107,7 @@ def Fire(component=None, command=None, name=None, serialize=None):
   name = name or os.path.basename(sys.argv[0])
 
   # Get args as a list.
-  if isinstance(command, six.string_types):
+  if isinstance(command, str):
     args = shlex.split(command)
   elif isinstance(command, (list, tuple)):
     args = command
@@ -344,7 +342,7 @@ def _DictAsString(result, verbose=False):
 def _OneLineResult(result):
   """Returns result serialized to a single line string."""
   # TODO(dbieber): Ensure line is fewer than eg 120 characters.
-  if isinstance(result, six.string_types):
+  if isinstance(result, str):
     return str(result).replace('\n', ' ')
 
   # TODO(dbieber): Show a small amount of usage information about the function
diff --git a/fire/core_test.py b/fire/core_test.py
index b9033c22..9e1f7dba 100644
--- a/fire/core_test.py
+++ b/fire/core_test.py
@@ -20,8 +20,6 @@
 from fire import trace
 import mock
 
-import six
-
 
 class CoreTest(testutils.BaseTestCase):
 
@@ -214,13 +212,11 @@ def serialize(x):
     with self.assertRaises(core.FireError):
       core.Fire(ident, command=['asdf'], serialize=55)
 
-  @testutils.skipIf(six.PY2, 'lru_cache is Python 3 only.')
   def testLruCacheDecoratorBoundArg(self):
     self.assertEqual(
         core.Fire(tc.py3.LruCacheDecoratedMethod,  # pytype: disable=module-attr
                   command=['lru_cache_in_class', 'foo']), 'foo')
 
-  @testutils.skipIf(six.PY2, 'lru_cache is Python 3 only.')
   def testLruCacheDecorator(self):
     self.assertEqual(
         core.Fire(tc.py3.lru_cache_decorated,  # pytype: disable=module-attr
diff --git a/fire/custom_descriptions.py b/fire/custom_descriptions.py
index f7df90b0..768f0e23 100644
--- a/fire/custom_descriptions.py
+++ b/fire/custom_descriptions.py
@@ -37,7 +37,6 @@
 """
 
 from fire import formatting
-import six
 
 TWO_DOUBLE_QUOTES = '""'
 STRING_DESC_PREFIX = 'The string '
@@ -60,13 +59,11 @@ def NeedsCustomDescription(component):
     Whether the component should use a custom description and summary.
   """
   type_ = type(component)
-  if (type_ in six.string_types
-      or type_ in six.integer_types
-      or type_ is six.text_type
-      or type_ is six.binary_type
+  if (
+      type_ in (str, int, bytes)
       or type_ in (float, complex, bool)
       or type_ in (dict, tuple, list, set, frozenset)
-     ):
+  ):
     return True
   return False
 
diff --git a/fire/fire_test.py b/fire/fire_test.py
index 6b9a2fa2..74b3bb25 100644
--- a/fire/fire_test.py
+++ b/fire/fire_test.py
@@ -22,7 +22,6 @@
 from fire import testutils
 
 import mock
-import six
 
 
 class FireTest(testutils.BaseTestCase):
@@ -180,7 +179,6 @@ def testFireAnnotatedArgs(self):
     self.assertEqual(fire.Fire(tc.Annotations, command=['double', '5']), 10)
     self.assertEqual(fire.Fire(tc.Annotations, command=['triple', '5']), 15)
 
-  @testutils.skipIf(six.PY2, 'Keyword-only arguments not in Python 2.')
   def testFireKeywordOnlyArgs(self):
     with self.assertRaisesFireExit(2):
       # Keyword arguments must be passed with flag syntax.
@@ -717,7 +715,6 @@ def testHelpKwargsDecorator(self):
     with self.assertRaisesFireExit(0):
       fire.Fire(tc.decorated_method, command=['--help'])
 
-  @testutils.skipIf(six.PY2, 'Asyncio not available in Python 2.')
   def testFireAsyncio(self):
     self.assertEqual(fire.Fire(tc.py3.WithAsyncio,
                                command=['double', '--count', '10']), 20)
diff --git a/fire/helptext_test.py b/fire/helptext_test.py
index 9a0f4f6d..2250f199 100644
--- a/fire/helptext_test.py
+++ b/fire/helptext_test.py
@@ -23,7 +23,6 @@
 from fire import test_components as tc
 from fire import testutils
 from fire import trace
-import six
 
 
 class HelpTest(testutils.BaseTestCase):
@@ -276,8 +275,6 @@ def testHelpTextNoInit(self):
     self.assertIn('NAME\n    OldStyleEmpty', help_screen)
     self.assertIn('SYNOPSIS\n    OldStyleEmpty', help_screen)
 
-  @testutils.skipIf(
-      six.PY2, 'Python 2 does not support keyword-only arguments.')
   def testHelpTextKeywordOnlyArgumentsWithDefault(self):
     component = tc.py3.KeywordOnly.with_default  # pytype: disable=module-attr
     output = helptext.HelpText(
@@ -285,8 +282,6 @@ def testHelpTextKeywordOnlyArgumentsWithDefault(self):
     self.assertIn('NAME\n    with_default', output)
     self.assertIn('FLAGS\n    -x, --x=X', output)
 
-  @testutils.skipIf(
-      six.PY2, 'Python 2 does not support keyword-only arguments.')
   def testHelpTextKeywordOnlyArgumentsWithoutDefault(self):
     component = tc.py3.KeywordOnly.double  # pytype: disable=module-attr
     output = helptext.HelpText(
@@ -294,9 +289,6 @@ def testHelpTextKeywordOnlyArgumentsWithoutDefault(self):
     self.assertIn('NAME\n    double', output)
     self.assertIn('FLAGS\n    -c, --count=COUNT (required)', output)
 
-  @testutils.skipIf(
-      six.PY2,
-      'Python 2 does not support required name-only arguments.')
   def testHelpTextFunctionMixedDefaults(self):
     component = tc.py3.HelpTextComponent().identity
     t = trace.FireTrace(component, name='FunctionMixedDefaults')
@@ -523,9 +515,6 @@ def testUsageOutputFunctionWithDocstring(self):
         textwrap.dedent(expected_output).lstrip('\n'),
         usage_output)
 
-  @testutils.skipIf(
-      six.PY2,
-      'Python 2 does not support required name-only arguments.')
   def testUsageOutputFunctionMixedDefaults(self):
     component = tc.py3.HelpTextComponent().identity
     t = trace.FireTrace(component, name='FunctionMixedDefaults')
diff --git a/fire/inspectutils.py b/fire/inspectutils.py
index ca51a9a5..0d0b048d 100644
--- a/fire/inspectutils.py
+++ b/fire/inspectutils.py
@@ -20,10 +20,7 @@
 
 from fire import docstrings
 
-import six
-
-if six.PY34:
-  import asyncio  # pylint: disable=import-error,g-import-not-at-top  # pytype: disable=import-error
+import asyncio  # pylint: disable=import-error,g-import-not-at-top  # pytype: disable=import-error
 
 
 class FullArgSpec(object):
@@ -74,8 +71,6 @@ class with an __init__ method.
   if inspect.isclass(fn):
     # If the function is a class, we try to use its init method.
     skip_arg = True
-    if six.PY2 and hasattr(fn, '__init__'):
-      fn = fn.__init__
   elif inspect.ismethod(fn):
     # If the function is a bound method, we skip the `self` argument.
     skip_arg = fn.__self__ is not None
@@ -91,16 +86,6 @@ class with an __init__ method.
   return fn, skip_arg
 
 
-def Py2GetArgSpec(fn):
-  """A wrapper around getargspec that tries both fn and fn.__call__."""
-  try:
-    return inspect.getargspec(fn)  # pylint: disable=deprecated-method,no-member
-  except TypeError:
-    if hasattr(fn, '__call__'):
-      return inspect.getargspec(fn.__call__)  # pylint: disable=deprecated-method,no-member
-    raise
-
-
 def Py3GetFullArgSpec(fn):
   """A alternative to the builtin getfullargspec.
 
@@ -185,13 +170,9 @@ def GetFullArgSpec(fn):
     if sys.version_info[0:2] >= (3, 5):
       (args, varargs, varkw, defaults,
        kwonlyargs, kwonlydefaults, annotations) = Py3GetFullArgSpec(fn)
-    elif six.PY3:  # Specifically Python 3.4.
+    else:  # Specifically Python 3.4.
       (args, varargs, varkw, defaults,
        kwonlyargs, kwonlydefaults, annotations) = inspect.getfullargspec(fn)  # pylint: disable=deprecated-method,no-member
-    else:  # six.PY2
-      args, varargs, varkw, defaults = Py2GetArgSpec(fn)
-      kwonlyargs = kwonlydefaults = None
-      annotations = getattr(fn, '__annotations__', None)
 
   except TypeError:
     # If we can't get the argspec, how do we know if the fn should take args?
@@ -221,7 +202,7 @@ def GetFullArgSpec(fn):
     return FullArgSpec()
 
   # In Python 3.5+ Py3GetFullArgSpec uses skip_bound_arg=True already.
-  skip_arg_required = six.PY2 or sys.version_info[0:2] == (3, 4)
+  skip_arg_required = sys.version_info[0:2] == (3, 4)
   if skip_arg_required and skip_arg and args:
     args.pop(0)  # Remove 'self' or 'cls' from the list of arguments.
   return FullArgSpec(args, varargs, varkw, defaults,
@@ -363,6 +344,6 @@ def GetClassAttrsDict(component):
 
 def IsCoroutineFunction(fn):
   try:
-    return six.PY34 and asyncio.iscoroutinefunction(fn)
+    return asyncio.iscoroutinefunction(fn)
   except:  # pylint: disable=bare-except
     return False
diff --git a/fire/inspectutils_test.py b/fire/inspectutils_test.py
index bb62f402..47de7e72 100644
--- a/fire/inspectutils_test.py
+++ b/fire/inspectutils_test.py
@@ -15,14 +15,11 @@
 """Tests for the inspectutils module."""
 
 import os
-import unittest
 
 from fire import inspectutils
 from fire import test_components as tc
 from fire import testutils
 
-import six
-
 
 class InspectUtilsTest(testutils.BaseTestCase):
 
@@ -36,7 +33,6 @@ def testGetFullArgSpec(self):
     self.assertEqual(spec.kwonlydefaults, {})
     self.assertEqual(spec.annotations, {'arg2': int, 'arg4': int})
 
-  @unittest.skipIf(six.PY2, 'No keyword arguments in python 2')
   def testGetFullArgSpecPy3(self):
     spec = inspectutils.GetFullArgSpec(tc.py3.identity)
     self.assertEqual(spec.args, ['arg1', 'arg2', 'arg3', 'arg4'])
@@ -121,10 +117,7 @@ def testInfoClass(self):
 
   def testInfoClassNoInit(self):
     info = inspectutils.Info(tc.OldStyleEmpty)
-    if six.PY2:
-      self.assertEqual(info.get('type_name'), 'classobj')
-    else:
-      self.assertEqual(info.get('type_name'), 'type')
+    self.assertEqual(info.get('type_name'), 'type')
     self.assertIn(os.path.join('fire', 'test_components.py'), info.get('file'))
     self.assertGreater(info.get('line'), 0)
 
diff --git a/fire/parser_fuzz_test.py b/fire/parser_fuzz_test.py
index 38e17725..9739ec4e 100644
--- a/fire/parser_fuzz_test.py
+++ b/fire/parser_fuzz_test.py
@@ -21,7 +21,6 @@
 from hypothesis import settings
 from hypothesis import strategies as st
 import Levenshtein
-import six
 
 
 class ParserFuzzTest(testutils.BaseTestCase):
@@ -64,8 +63,8 @@ def testDefaultParseValueFuzz(self, value):
       raise
 
     try:
-      uvalue = six.text_type(value)
-      uresult = six.text_type(result)
+      uvalue = str(value)
+      uresult = str(result)
     except UnicodeDecodeError:
       # This is not what we're testing.
       return
@@ -82,7 +81,7 @@ def testDefaultParseValueFuzz(self, value):
     if '#' in value:
       max_distance += len(value) - value.index('#')
 
-    if not isinstance(result, six.string_types):
+    if not isinstance(result, str):
       max_distance += value.count('0')  # Leading 0s are stripped.
 
     # Note: We don't check distance for dicts since item order can be changed.
diff --git a/fire/test_components.py b/fire/test_components.py
index e50f647c..540a9e16 100644
--- a/fire/test_components.py
+++ b/fire/test_components.py
@@ -18,10 +18,7 @@
 import enum
 import functools
 
-import six
-
-if six.PY3:
-  from fire import test_components_py3 as py3  # pylint: disable=unused-import,no-name-in-module,g-import-not-at-top
+from fire import test_components_py3 as py3  # pylint: disable=unused-import,no-name-in-module,g-import-not-at-top
 
 
 def identity(arg1, arg2, arg3=10, arg4=20, *arg5, **arg6):  # pylint: disable=keyword-arg-before-vararg
diff --git a/fire/testutils.py b/fire/testutils.py
index 76faa3f4..fa1ca86d 100644
--- a/fire/testutils.py
+++ b/fire/testutils.py
@@ -15,6 +15,7 @@
 """Utilities for Python Fire's tests."""
 
 import contextlib
+import io
 import os
 import re
 import sys
@@ -24,7 +25,6 @@
 from fire import trace
 
 import mock
-import six
 
 
 class BaseTestCase(unittest.TestCase):
@@ -45,8 +45,8 @@ def assertOutputMatches(self, stdout='.*', stderr='.*', capture=True):
     Yields:
       Yields to the wrapped context.
     """
-    stdout_fp = six.StringIO()
-    stderr_fp = six.StringIO()
+    stdout_fp = io.StringIO()
+    stderr_fp = io.StringIO()
     try:
       with mock.patch.object(sys, 'stdout', stdout_fp):
         with mock.patch.object(sys, 'stderr', stderr_fp):
@@ -69,10 +69,7 @@ def assertOutputMatches(self, stdout='.*', stderr='.*', capture=True):
                                (name, value, regexp))
 
   def assertRaisesRegex(self, *args, **kwargs):  # pylint: disable=arguments-differ
-    if sys.version_info.major == 2:
-      return super(BaseTestCase, self).assertRaisesRegexp(*args, **kwargs)  # pylint: disable=deprecated-method,no-member
-    else:
-      return super(BaseTestCase, self).assertRaisesRegex(*args, **kwargs)  # pylint: disable=no-member
+    return super(BaseTestCase, self).assertRaisesRegex(*args, **kwargs)  # pylint: disable=no-member
 
   @contextlib.contextmanager
   def assertRaisesFireExit(self, code, regexp='.*'):
diff --git a/fire/testutils_test.py b/fire/testutils_test.py
index 0999a4c8..4cfc0937 100644
--- a/fire/testutils_test.py
+++ b/fire/testutils_test.py
@@ -18,8 +18,6 @@
 
 from fire import testutils
 
-import six
-
 
 class TestTestUtils(testutils.BaseTestCase):
   """Let's get meta."""
@@ -30,15 +28,15 @@ def testNoCheckOnException(self):
         raise ValueError()
 
   def testCheckStdoutOrStderrNone(self):
-    with six.assertRaisesRegex(self, AssertionError, 'stdout:'):
+    with self.assertRaisesRegex(AssertionError, 'stdout:'):
       with self.assertOutputMatches(stdout=None):
         print('blah')
 
-    with six.assertRaisesRegex(self, AssertionError, 'stderr:'):
+    with self.assertRaisesRegex(AssertionError, 'stderr:'):
       with self.assertOutputMatches(stderr=None):
         print('blah', file=sys.stderr)
 
-    with six.assertRaisesRegex(self, AssertionError, 'stderr:'):
+    with self.assertRaisesRegex(AssertionError, 'stderr:'):
       with self.assertOutputMatches(stdout='apple', stderr=None):
         print('apple')
         print('blah', file=sys.stderr)
diff --git a/fire/value_types.py b/fire/value_types.py
index b2d0a0b3..81308973 100644
--- a/fire/value_types.py
+++ b/fire/value_types.py
@@ -17,10 +17,9 @@
 import inspect
 
 from fire import inspectutils
-import six
 
 
-VALUE_TYPES = (bool, six.string_types, six.integer_types, float, complex,
+VALUE_TYPES = (bool, str, bytes, int, float, complex,
                type(Ellipsis), type(None), type(NotImplemented))