diff --git a/.ci/travis/install.sh b/.ci/travis/install.sh
index 677dc4653..a31cb2d85 100755
--- a/.ci/travis/install.sh
+++ b/.ci/travis/install.sh
@@ -41,9 +41,7 @@ if [[ "$(uname -s)" == 'Darwin' ]]; then
     pyenv activate psutil
 fi
 
-if [[ $TRAVIS_PYTHON_VERSION == '2.6' ]] || [[ $PYVER == 'py26' ]]; then
-    pip install -U ipaddress unittest2 argparse mock==1.0.1
-elif [[ $TRAVIS_PYTHON_VERSION == '2.7' ]] || [[ $PYVER == 'py27' ]]; then
+if [[ $TRAVIS_PYTHON_VERSION == '2.7' ]] || [[ $PYVER == 'py27' ]]; then
     pip install -U ipaddress mock
 elif [[ $TRAVIS_PYTHON_VERSION == '3.2' ]] || [[ $PYVER == 'py32' ]]; then
     pip install -U ipaddress mock
diff --git a/DEVGUIDE.rst b/DEVGUIDE.rst
index c4ddc52d7..703ccf472 100644
--- a/DEVGUIDE.rst
+++ b/DEVGUIDE.rst
@@ -40,7 +40,7 @@ Makefile
 Some useful make commands::
 
   $ make install        # install
-  $ make setup-dev-env  # install useful dev libs (pyflakes, unittest2, etc.)
+  $ make setup-dev-env  # install useful dev libs (pyflakes, mock, etc.)
   $ make test           # run unit tests
   $ make test-memleaks  # run memory leak tests
   $ make coverage       # run test coverage
diff --git a/Makefile b/Makefile
index 953225e3e..fdf47f6d9 100644
--- a/Makefile
+++ b/Makefile
@@ -14,7 +14,7 @@ DEPS = \
 	flake8 \
 	futures \
 	ipaddress \
-	mock==1.0.1 \
+	mock \
 	pep8 \
 	perf \
 	pyflakes \
@@ -22,7 +22,6 @@ DEPS = \
 	setuptools \
 	sphinx \
 	twine \
-	unittest2 \
 	requests
 
 # In not in a virtualenv, add --user options for install commands.
diff --git a/appveyor.yml b/appveyor.yml
index af7a63192..b5d01f0a1 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -78,13 +78,11 @@ install:
   - "powershell .ci\\appveyor\\install.ps1"
   # - ps: (new-object net.webclient).DownloadFile('https://raw.github.com/pypa/pip/master/contrib/get-pip.py', 'C:/get-pip.py')
   - "%WITH_COMPILER% %PYTHON%/python.exe -m pip --version"
-  - "%WITH_COMPILER% %PYTHON%/python.exe -m pip install --upgrade --user unittest2 ipaddress pypiwin32 wmi wheel"
   - "%WITH_COMPILER% %PYTHON%/python.exe -m pip freeze"
   - "%WITH_COMPILER% %PYTHON%/python.exe setup.py build"
   - "%WITH_COMPILER% %PYTHON%/python.exe setup.py build build_ext -i"
   - "%WITH_COMPILER% %PYTHON%/python.exe setup.py develop"
-  # 1.0.1 is the latest release supporting python 2.6
-  - "%WITH_COMPILER% %PYTHON%/Scripts/pip.exe install mock==1.0.1"
+  - "%WITH_COMPILER% %PYTHON%/Scripts/pip.exe install mock"
 
 build: off
 
diff --git a/psutil/tests/__init__.py b/psutil/tests/__init__.py
index 2546f98c7..e63f8e682 100644
--- a/psutil/tests/__init__.py
+++ b/psutil/tests/__init__.py
@@ -26,6 +26,7 @@
 import textwrap
 import threading
 import time
+import unittest
 import warnings
 from socket import AF_INET
 from socket import AF_INET6
@@ -41,11 +42,6 @@
 from psutil._compat import unicode
 from psutil._compat import which
 
-if sys.version_info < (2, 7):
-    import unittest2 as unittest  # requires "pip install unittest2"
-else:
-    import unittest
-
 try:
     from unittest import mock  # py3
 except ImportError:
diff --git a/psutil/tests/__main__.py b/psutil/tests/__main__.py
index 1490e6b6e..af084499c 100755
--- a/psutil/tests/__main__.py
+++ b/psutil/tests/__main__.py
@@ -16,12 +16,12 @@
 import ssl
 import sys
 import tempfile
+import unittest
 try:
     from urllib.request import urlopen  # py3
 except ImportError:
     from urllib2 import urlopen
 
-from psutil.tests import unittest
 from psutil.tests import VERBOSITY
 
 
diff --git a/psutil/tests/test_bsd.py b/psutil/tests/test_bsd.py
index 8fd7fe1d5..2d148140a 100755
--- a/psutil/tests/test_bsd.py
+++ b/psutil/tests/test_bsd.py
@@ -14,6 +14,7 @@
 import os
 import re
 import time
+import unittest
 
 import psutil
 from psutil import BSD
@@ -26,7 +27,6 @@
 from psutil.tests import retry_before_failing
 from psutil.tests import run_test_module_by_name
 from psutil.tests import sh
-from psutil.tests import unittest
 from psutil.tests import which
 
 
diff --git a/psutil/tests/test_connections.py b/psutil/tests/test_connections.py
index c34210002..b68c87f3b 100755
--- a/psutil/tests/test_connections.py
+++ b/psutil/tests/test_connections.py
@@ -9,6 +9,7 @@
 import os
 import socket
 import textwrap
+import unittest
 from contextlib import closing
 from socket import AF_INET
 from socket import AF_INET6
@@ -39,7 +40,6 @@
 from psutil.tests import skip_on_access_denied
 from psutil.tests import tcp_socketpair
 from psutil.tests import TESTFN
-from psutil.tests import unittest
 from psutil.tests import unix_socket_path
 from psutil.tests import unix_socketpair
 from psutil.tests import wait_for_file
diff --git a/psutil/tests/test_contracts.py b/psutil/tests/test_contracts.py
index 7666f2f83..a3fd07003 100755
--- a/psutil/tests/test_contracts.py
+++ b/psutil/tests/test_contracts.py
@@ -14,6 +14,7 @@
 import stat
 import time
 import traceback
+import unittest
 from contextlib import closing
 
 from psutil import BSD
@@ -38,7 +39,6 @@
 from psutil.tests import safe_rmpath
 from psutil.tests import skip_on_access_denied
 from psutil.tests import TESTFN
-from psutil.tests import unittest
 from psutil.tests import unix_socket_path
 from psutil.tests import VALID_PROC_STATUSES
 from psutil.tests import warn
diff --git a/psutil/tests/test_linux.py b/psutil/tests/test_linux.py
index 053c5f692..82a0121a9 100755
--- a/psutil/tests/test_linux.py
+++ b/psutil/tests/test_linux.py
@@ -21,6 +21,7 @@
 import tempfile
 import textwrap
 import time
+import unittest
 import warnings
 
 import psutil
@@ -44,7 +45,6 @@
 from psutil.tests import TESTFN
 from psutil.tests import ThreadTask
 from psutil.tests import TRAVIS
-from psutil.tests import unittest
 from psutil.tests import which
 
 
diff --git a/psutil/tests/test_memory_leaks.py b/psutil/tests/test_memory_leaks.py
index 28a083f26..c3727763b 100755
--- a/psutil/tests/test_memory_leaks.py
+++ b/psutil/tests/test_memory_leaks.py
@@ -19,6 +19,7 @@
 import os
 import threading
 import time
+import unittest
 
 import psutil
 import psutil._common
@@ -46,7 +47,6 @@
 from psutil.tests import safe_rmpath
 from psutil.tests import TESTFN
 from psutil.tests import TRAVIS
-from psutil.tests import unittest
 
 
 LOOPS = 1000
diff --git a/psutil/tests/test_misc.py b/psutil/tests/test_misc.py
index 6bc2e28c9..e905770f2 100755
--- a/psutil/tests/test_misc.py
+++ b/psutil/tests/test_misc.py
@@ -20,6 +20,7 @@
 import socket
 import stat
 import sys
+import unittest
 
 from psutil import LINUX
 from psutil import POSIX
@@ -57,7 +58,6 @@
 from psutil.tests import TESTFN
 from psutil.tests import TOX
 from psutil.tests import TRAVIS
-from psutil.tests import unittest
 from psutil.tests import unix_socket_path
 from psutil.tests import unix_socketpair
 from psutil.tests import wait_for_file
diff --git a/psutil/tests/test_osx.py b/psutil/tests/test_osx.py
index 8ba949b0a..1b9fc1349 100755
--- a/psutil/tests/test_osx.py
+++ b/psutil/tests/test_osx.py
@@ -9,6 +9,7 @@
 import os
 import re
 import time
+import unittest
 
 import psutil
 from psutil import OSX
@@ -18,7 +19,6 @@
 from psutil.tests import retry_before_failing
 from psutil.tests import run_test_module_by_name
 from psutil.tests import sh
-from psutil.tests import unittest
 
 
 PAGESIZE = os.sysconf("SC_PAGE_SIZE") if OSX else None
diff --git a/psutil/tests/test_posix.py b/psutil/tests/test_posix.py
index 3274c02ca..8a1c59d85 100755
--- a/psutil/tests/test_posix.py
+++ b/psutil/tests/test_posix.py
@@ -13,6 +13,7 @@
 import subprocess
 import sys
 import time
+import unittest
 
 import psutil
 from psutil import BSD
@@ -34,7 +35,6 @@
 from psutil.tests import sh
 from psutil.tests import skip_on_access_denied
 from psutil.tests import TRAVIS
-from psutil.tests import unittest
 from psutil.tests import wait_for_pid
 
 
diff --git a/psutil/tests/test_process.py b/psutil/tests/test_process.py
index d1cb96573..39e804c06 100755
--- a/psutil/tests/test_process.py
+++ b/psutil/tests/test_process.py
@@ -20,6 +20,7 @@
 import textwrap
 import time
 import types
+import unittest
 
 import psutil
 
@@ -65,7 +66,6 @@
 from psutil.tests import ThreadTask
 from psutil.tests import TOX
 from psutil.tests import TRAVIS
-from psutil.tests import unittest
 from psutil.tests import wait_for_pid
 from psutil.tests import WIN_VISTA
 
diff --git a/psutil/tests/test_sunos.py b/psutil/tests/test_sunos.py
index ea9afcde0..995acd60d 100755
--- a/psutil/tests/test_sunos.py
+++ b/psutil/tests/test_sunos.py
@@ -7,12 +7,12 @@
 """Sun OS specific tests."""
 
 import os
+import unittest
 
 import psutil
 from psutil import SUNOS
 from psutil.tests import run_test_module_by_name
 from psutil.tests import sh
-from psutil.tests import unittest
 
 
 @unittest.skipIf(not SUNOS, "SUNOS only")
diff --git a/psutil/tests/test_system.py b/psutil/tests/test_system.py
index 32f76f57c..accfe83ca 100755
--- a/psutil/tests/test_system.py
+++ b/psutil/tests/test_system.py
@@ -17,6 +17,7 @@
 import sys
 import tempfile
 import time
+import unittest
 
 import psutil
 from psutil import BSD
@@ -48,7 +49,6 @@
 from psutil.tests import TESTFN
 from psutil.tests import TESTFN_UNICODE
 from psutil.tests import TRAVIS
-from psutil.tests import unittest
 
 
 # ===================================================================
diff --git a/psutil/tests/test_unicode.py b/psutil/tests/test_unicode.py
index ae3c012fd..0177dfbad 100755
--- a/psutil/tests/test_unicode.py
+++ b/psutil/tests/test_unicode.py
@@ -53,6 +53,7 @@
 """
 
 import os
+import unittest
 from contextlib import closing
 
 from psutil import BSD
@@ -79,7 +80,6 @@
 from psutil.tests import TESTFN
 from psutil.tests import TESTFN_UNICODE
 from psutil.tests import TRAVIS
-from psutil.tests import unittest
 from psutil.tests import unix_socket_path
 import psutil
 import psutil.tests
diff --git a/psutil/tests/test_windows.py b/psutil/tests/test_windows.py
index ac7872837..b60a950dc 100755
--- a/psutil/tests/test_windows.py
+++ b/psutil/tests/test_windows.py
@@ -16,6 +16,7 @@
 import subprocess
 import sys
 import time
+import unittest
 
 try:
     import win32api  # requires "pip install pypiwin32" / "make setup-dev-env"
@@ -37,7 +38,6 @@
 from psutil.tests import retry_before_failing
 from psutil.tests import run_test_module_by_name
 from psutil.tests import sh
-from psutil.tests import unittest
 
 
 cext = psutil._psplatform.cext
diff --git a/scripts/internal/winmake.py b/scripts/internal/winmake.py
index aaeaeed56..b1c529899 100755
--- a/scripts/internal/winmake.py
+++ b/scripts/internal/winmake.py
@@ -40,7 +40,6 @@
     "pypiwin32",
     "pyreadline",
     "setuptools",
-    "unittest2",
     "wheel",
     "wmi",
     "requests"
diff --git a/setup.py b/setup.py
index 0b26fc220..2ca466a2d 100755
--- a/setup.py
+++ b/setup.py
@@ -270,7 +270,7 @@ def main():
         packages=packages,
         ext_modules=extensions,
         test_suite="psutil.tests.get_suite",
-        tests_require=['ipaddress', 'mock', 'unittest2'],
+        tests_require=['ipaddress', 'mock'],
         zip_safe=False,   # http://stackoverflow.com/questions/19548957
         # see: python setup.py register --list-classifiers
         classifiers=[
diff --git a/tox.ini b/tox.ini
index 20b9f229d..f64125fa8 100644
--- a/tox.ini
+++ b/tox.ini
@@ -5,14 +5,11 @@
 # directory.
 
 [tox]
-envlist = py26, py27, py32, py33, py34
+envlist = py27, py32, py33, py34, py35, py36
 
 [testenv]
 deps =
     flake8
-    py26: ipaddress
-    py26: mock==1.0.1
-    py26: unittest2
     py27: ipaddress
     py27: mock
     py32: ipaddress