--- a/testtools/tests/test_run.py
+++ b/testtools/tests/test_run.py
@@ -10,7 +10,7 @@ from textwrap import dedent
 from extras import try_import
 fixtures = try_import('fixtures')
 testresources = try_import('testresources')
-import unittest2
+import unittest
 
 import testtools
 from testtools import TestCase, run, skipUnless
@@ -195,13 +195,13 @@ testtools.runexample.TestFoo.test_quux
         broken = self.useFixture(SampleTestFixture(broken=True))
         out = StringIO()
         # XXX: http://bugs.python.org/issue22811
-        unittest2.defaultTestLoader._top_level_dir = None
+        unittest.defaultTestLoader._top_level_dir = None
         exc = self.assertRaises(
             SystemExit,
             run.main, ['prog', 'discover', '-l', broken.package.base, '*.py'], out)
         self.assertEqual(2, exc.args[0])
         self.assertThat(out.getvalue(), DocTestMatches("""\
-unittest2.loader._FailedTest.runexample
+unittest.loader._FailedTest.runexample
 Failed to import test module: runexample
 Traceback (most recent call last):
   File ".../loader.py", line ..., in _find_test_path
@@ -345,7 +345,7 @@ OK
         pkg = self.useFixture(SampleLoadTestsPackage())
         out = StringIO()
         # XXX: http://bugs.python.org/issue22811
-        unittest2.defaultTestLoader._top_level_dir = None
+        unittest.defaultTestLoader._top_level_dir = None
         self.assertEqual(None, run.main(
             ['prog', 'discover', '-l', pkg.package.base], out))
         self.assertEqual(dedent("""\
--- a/testtools/tests/test_testsuite.py
+++ b/testtools/tests/test_testsuite.py
@@ -5,7 +5,6 @@
 import doctest
 from pprint import pformat
 import unittest
-import unittest2
 
 from extras import try_import
 
@@ -225,7 +224,7 @@ TypeError: run() takes ...1 ...argument.
                 pass
         # Test discovery uses the default suite from unittest2 (unless users
         # deliberately change things, in which case they keep both pieces).
-        suite = unittest2.TestSuite([Skips("test_notrun")])
+        suite = unittest.TestSuite([Skips("test_notrun")])
         log = []
         result = LoggingResult(log)
         suite.run(result)
@@ -242,7 +241,7 @@ TypeError: run() takes ...1 ...argument.
                 pass
         # Test discovery uses the default suite from unittest2 (unless users
         # deliberately change things, in which case they keep both pieces).
-        suite = unittest2.TestSuite([Simples("test_simple")])
+        suite = unittest.TestSuite([Simples("test_simple")])
         log = []
         result = LoggingResult(log)
         suite.run(result)
--- a/testtools/tests/twistedsupport/test_deferred.py
+++ b/testtools/tests/twistedsupport/test_deferred.py
@@ -52,5 +52,5 @@ class TestExtractResult(NeedsTwistedTest
 
 
 def test_suite():
-    from unittest2 import TestLoader, TestSuite
+    from unittest import TestLoader, TestSuite
     return TestLoader().loadTestsFromName(__name__)
--- a/testtools/tests/twistedsupport/test_matchers.py
+++ b/testtools/tests/twistedsupport/test_matchers.py
@@ -205,5 +205,5 @@ class FailureResultTests(NeedsTwistedTes
 
 
 def test_suite():
-    from unittest2 import TestLoader, TestSuite
+    from unittest import TestLoader, TestSuite
     return TestLoader().loadTestsFromName(__name__)
--- a/testtools/tests/twistedsupport/test_runtest.py
+++ b/testtools/tests/twistedsupport/test_runtest.py
@@ -1016,7 +1016,7 @@ class TestCaptureTwistedLogs(NeedsTwiste
 
 
 def test_suite():
-    from unittest2 import TestLoader, TestSuite
+    from unittest import TestLoader, TestSuite
     return TestLoader().loadTestsFromName(__name__)
 
 
--- a/testtools/run.py
+++ b/testtools/run.py
@@ -195,7 +195,10 @@ class TestProgram(unittest.TestProgram):
             else:
                 for test in iterate_tests(self.test):
                     self.stdout.write('%s\n' % test.id())
-        del self.testLoader.errors[:]
+        if hasattr(self.testLoader, 'errors'):
+            del self.testLoader.errors[:]
+        else:
+            self.testLoader.errors = []
 
     def _getParentArgParser(self):
         parser = super(TestProgram, self)._getParentArgParser()