diff --git a/git_review/cmd.py b/git_review/cmd.py
index 9607fd90..19adfae2 100644
--- a/git_review/cmd.py
+++ b/git_review/cmd.py
@@ -17,24 +17,22 @@
 from __future__ import print_function
 
 import argparse
+import configparser
 import datetime
 import getpass
 import json
 import os
 import re
 import shlex
-import six
 import subprocess
 import sys
 import textwrap
+from urllib.parse import urlencode
+from urllib.parse import urljoin
+from urllib.parse import urlparse
 
 import pkg_resources
 import requests
-from six.moves import configparser
-from six.moves import input as do_input
-from six.moves.urllib.parse import urlencode
-from six.moves.urllib.parse import urljoin
-from six.moves.urllib.parse import urlparse
 
 
 VERBOSE = False
@@ -138,11 +136,7 @@ def run_command_status(*argv, **kwargs):
     if VERBOSE:
         print(datetime.datetime.now(), "Running:", " ".join(argv))
     if len(argv) == 1:
-        # for python2 compatibility with shlex
-        if sys.version_info < (3,) and isinstance(argv[0], six.text_type):
-            argv = shlex.split(argv[0].encode('utf-8'))
-        else:
-            argv = shlex.split(str(argv[0]))
+        argv = shlex.split(str(argv[0]))
     stdin = kwargs.pop('stdin', None)
     newenv = os.environ.copy()
     newenv['LANG'] = 'C'
@@ -416,7 +410,7 @@ def add_remote(scheme, hostname, port, project, remote, usepushurl):
         print("No remote set, testing %s" % remote_url)
     if not test_remote_url(remote_url):
         print("Could not connect to gerrit.")
-        username = do_input("Enter your gerrit username: ")
+        username = input("Enter your gerrit username: ")
         remote_url = make_remote_url(scheme, username, hostname, port, project)
         print("Trying again with %s" % remote_url)
         if not test_remote_url(remote_url):
@@ -954,7 +948,7 @@ def assert_one_change(remote, branch, yes, have_hook):
                       "branches (for independent changes).")
             print("\nThe outstanding commits are:\n\n%s\n\n"
                   "Do you really want to submit the above commits?" % output)
-            yes_no = do_input("Type 'yes' to confirm, other to cancel: ")
+            yes_no = input("Type 'yes' to confirm, other to cancel: ")
             if yes_no.lower().strip() != "yes":
                 print("Aborting.")
                 sys.exit(1)
@@ -1729,15 +1723,6 @@ review.
 
 
 def main():
-    # workaround for avoiding UnicodeEncodeError on print() with older python
-    if sys.version_info[0] < 3:
-        # without reload print would fail even if sys.stdin.encoding
-        # would report utf-8
-        # see: https://stackoverflow.com/a/23847316/99834
-        stdin, stdout, stderr = sys.stdin, sys.stdout, sys.stderr
-        reload(sys)  # noqa
-        sys.stdin, sys.stdout, sys.stderr = stdin, stdout, stderr
-        sys.setdefaultencoding(os.environ.get('PYTHONIOENCODING', 'utf-8'))
 
     try:
         _main()
diff --git a/git_review/tests/test_unit.py b/git_review/tests/test_unit.py
index 553cfac2..0854ebc7 100644
--- a/git_review/tests/test_unit.py
+++ b/git_review/tests/test_unit.py
@@ -17,6 +17,7 @@
 
 import argparse
 import functools
+import io
 import os
 import sys
 import textwrap
@@ -29,13 +30,6 @@ from git_review import cmd
 from git_review.tests import IsoEnvDir
 from git_review.tests import utils
 
-# Use of io.StringIO in python =< 2.7 requires all strings handled to be
-# unicode. See if StringIO.StringIO is available first
-try:
-    import StringIO as io
-except ImportError:
-    import io
-
 
 class ConfigTestCase(testtools.TestCase):
     """Class testing config behavior."""
diff --git a/requirements.txt b/requirements.txt
index 289b82a4..944892c0 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,2 +1 @@
 requests>=1.1
-six
diff --git a/setup.cfg b/setup.cfg
index 85fe3642..dfeba852 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -4,8 +4,9 @@ summary = Tool to submit code to Gerrit
 description-file = README.rst
 license = Apache License (2.0)
 classifiers =
-    Programming Language :: Python :: 2
     Programming Language :: Python :: 3
+    Programming Language :: Python :: 3.5
+    Programming Language :: Python :: 3.6
     Programming Language :: Python
     Development Status :: 5 - Production/Stable
     Environment :: Console
@@ -19,6 +20,7 @@ author = OpenStack
 author-email = openstack-infra@lists.openstack.org
 home-page = http://docs.openstack.org/infra/git-review/
 project-url = http://docs.openstack.org/infra/
+python-requires = >= 3.5
 
 [files]
 packages =
diff --git a/setup.py b/setup.py
index 10d670de..66481e7d 100755
--- a/setup.py
+++ b/setup.py
@@ -17,4 +17,4 @@
 import setuptools
 
 
-setuptools.setup(setup_requires=['pbr'], pbr=True)
+setuptools.setup(setup_requires=['pbr>=4.1.0'], pbr=True)
diff --git a/tox.ini b/tox.ini
index 45e4541b..c5bae522 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,5 +1,5 @@
 [tox]
-envlist = linters,docs,py27,py3{4,5,6,7}
+envlist = linters,docs,py3{5,6,7}
 ignore_basepython_conflict = true
 
 [testenv]