diff --git a/.github/workflows/python.yml b/.github/workflows/python.yml
index 427f070..e6c98c6 100644
--- a/.github/workflows/python.yml
+++ b/.github/workflows/python.yml
@@ -7,10 +7,11 @@ on: [push, pull_request]
 
 jobs:
   build:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
     strategy:
+      fail-fast: false
       matrix:
-        python-version: [3.5, 3.6, 3.7, 3.8, 3.9, "pypy3"]
+        python-version: ["3.5", "3.6", "3.7", "3.8", "3.9", "3.10", "3.11", "pypy3"]
 
     steps:
       - uses: actions/checkout@v2
diff --git a/CHANGES.rst b/CHANGES.rst
index 0be7820..eb23369 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -4,6 +4,15 @@ premailer Changes
 Peter's note: Unfortunately, ``premailer`` didn't use to keep a change log. But it's
 never too late to start, so let's start here and now.
 
+Unreleased
+----------
+
+* Add support for Python 3.9, 3.10 and 3.11. The code for the distributed code was unchanged,
+  only some tests needed to be adapted.
+
+* Moved from nose test runner to pytest, as nose is no longer supported and has some known issues
+  with Python 3.9+.
+
 3.10.0
 ------
 
diff --git a/README.rst b/README.rst
index 1b6b8cc..320a7a9 100644
--- a/README.rst
+++ b/README.rst
@@ -30,6 +30,9 @@ makes sure premailer works in:
 -  Python 3.6
 -  Python 3.7
 -  Python 3.8
+-  Python 3.9
+-  Python 3.10
+-  Python 3.11
 -  PyPy
 
 Turns CSS blocks into style attributes
diff --git a/premailer/tests/test_premailer.py b/premailer/tests/test_premailer.py
index c1e803e..1a1772b 100644
--- a/premailer/tests/test_premailer.py
+++ b/premailer/tests/test_premailer.py
@@ -3,15 +3,15 @@
 import sys
 import os
 import unittest
+import tempfile
 from contextlib import contextmanager
 from io import StringIO
-import tempfile
+from unittest import mock
 
+import pytest
 from lxml.etree import XMLSyntaxError, fromstring
 from requests.exceptions import HTTPError
-import mock
 import premailer.premailer  # lint:ok
-from nose.tools import assert_raises, eq_, ok_
 from premailer.__main__ import main
 from premailer.premailer import (
     ExternalNotFoundError,
@@ -23,6 +23,32 @@
 )
 
 
+def ok_(expr, msg=None):
+    """
+    Shorthand for assert.
+
+    Copied from Nose.
+    """
+    if not expr:
+        raise AssertionError(msg)
+
+
+def eq_(a, b, msg=None):
+    """
+    Shorthand for 'assert a == b, "%r != %r" % (a, b).
+
+    Copied from Nose.
+    """
+    if not a == b:
+        raise AssertionError(msg or "%r != %r" % (a, b))
+
+
+def assert_raises(exc_class, func, *args):
+    """Compatibility with Nose API for pytest."""
+    with pytest.raises(exc_class):
+        func(*args)
+
+
 whitespace_between_tags = re.compile(r">\s*<")
 
 
diff --git a/setup.py b/setup.py
index 86a6cf4..68d5799 100644
--- a/setup.py
+++ b/setup.py
@@ -20,7 +20,7 @@ def find_version(*file_paths):
 
 install_requires = ["lxml", "cssselect", "cssutils", "requests", "cachetools"]
 
-tests_require = ["nose", "mock"]
+tests_require = ["pytest", "pytest-cov"]
 
 setup(
     name="premailer",
@@ -45,6 +45,9 @@ def find_version(*file_paths):
         "Programming Language :: Python :: 3.6",
         "Programming Language :: Python :: 3.7",
         "Programming Language :: Python :: 3.8",
+        "Programming Language :: Python :: 3.9",
+        "Programming Language :: Python :: 3.10",
+        "Programming Language :: Python :: 3.11",
         "Programming Language :: Python :: Implementation :: CPython",
         "Programming Language :: Python :: Implementation :: PyPy",
         "Topic :: Communications",
diff --git a/tox.ini b/tox.ini
index 3d33e62..11d79a7 100644
--- a/tox.ini
+++ b/tox.ini
@@ -6,6 +6,8 @@ envlist =
     py37,
     py38,
     py39,
+    py310,
+    py311,
     pypy3,
 
 [gh-actions]
@@ -15,6 +17,8 @@ python =
   3.7: py37
   3.8: py38
   3.9: py39, lint
+  3.10: py310
+  3.11: py311
   pypy3: pypy3
 
 [testenv]
@@ -24,7 +28,7 @@ install_command =
 extras =
     test
 commands =
-    nosetests --with-coverage --cover-package=premailer
+    pytest --cov=premailer
 
 [testenv:lint-py39]
 extras = dev