diff --git a/.github/workflows/cicd.yml b/.github/workflows/cicd.yml
index 1f274c4b1..a1b446ed7 100644
--- a/.github/workflows/cicd.yml
+++ b/.github/workflows/cicd.yml
@@ -196,18 +196,15 @@ jobs:
         python-version: ["3.7", "3.9", "pypy-3.8"]
         twisted: ["19.2", "20.3", "current"]
         optional: [false]
-
-        #
-        # Including the following matrix addition results in the "Run unit
-        # tests" step hanging in a queued state for 30+ minutes.  We should put
-        # it back at some point.
-        #
-
-        # include:
-        #   - os: "ubuntu-latest"
-        #     python-version: "3.10"
-        #     twisted: "trunk"
-        #     optional: true
+        include:
+          - os: "ubuntu-latest"
+            python-version: "3.10"
+            twisted: "current"
+            optional: false
+          - os: "ubuntu-latest"
+            python-version: "3.11"
+            twisted: "current"
+            optional: false
 
     steps:
 
diff --git a/NEWS.rst b/NEWS.rst
index 322e5749b..bf34a803d 100644
--- a/NEWS.rst
+++ b/NEWS.rst
@@ -5,6 +5,9 @@ NEXT
 ----
 
  * Fixed a compatibility issue with Werkzeug versions greater than 2.2. [`#575 <https://github.com/twisted/klein/pull/575>`]
+ * Added explicit support for Python 3.10 and 3.11, although in practice they did work previously in 21.8. [`#578 <https://github.com/twisted/klein/pull/578>`]
+ * Python 3.6 is no longer supported by Klein.
+
 
 21.8.0 - 2021-08-08
 -------------------
diff --git a/setup.py b/setup.py
index 2c13f583f..623df6824 100644
--- a/setup.py
+++ b/setup.py
@@ -13,10 +13,11 @@
             "License :: OSI Approved :: MIT License",
             "Operating System :: OS Independent",
             "Programming Language :: Python",
-            "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 :: Internet :: WWW/HTTP :: Dynamic Content",
@@ -25,7 +26,7 @@
         description="werkzeug + twisted.web",
         long_description=long_description,
         long_description_content_type="text/x-rst",
-        python_requires=">=3.5",
+        python_requires=">=3.7",
         setup_requires=["incremental"],
         use_incremental=True,
         install_requires=[
diff --git a/tox.ini b/tox.ini
index ab1055c2e..644d38725 100644
--- a/tox.ini
+++ b/tox.ini
@@ -3,6 +3,7 @@
 envlist =
     lint, mypy
     coverage-py{36,37,38,39,310,py3}-tw{192,203,current,trunk}
+    coverage-py311-tw{current,trunk}
     coverage_report
     docs, docs-linkcheck
     packaging
@@ -52,7 +53,7 @@ basepython =
     py38: python3.8
     py39: python3.9
     py310: python3.10
-
+    py311: python3.11
     pypy3: pypy3
     pypy38: pypy3.8