diff --git a/.github/workflows/release-to-pypi.yml b/.github/workflows/release-to-pypi.yml
index f3a0d5b44..c2668cbc5 100644
--- a/.github/workflows/release-to-pypi.yml
+++ b/.github/workflows/release-to-pypi.yml
@@ -27,7 +27,7 @@ jobs:
     - name: Set up Python
       uses: actions/setup-python@v2
       with:
-        python-version: 3.8
+        python-version: '3.8'
 
     - name: Install Python packages needed for wheel build and upload
       run: |
@@ -60,7 +60,7 @@ jobs:
     - name: Set up Python
       uses: actions/setup-python@v2
       with:
-        python-version: 3.8
+        python-version: '3.8'
 
     - name: Install Python packages needed for sdist build and upload
       run: |
diff --git a/.github/workflows/run-core-traits-tests.yml b/.github/workflows/run-core-traits-tests.yml
index 098c49116..0f9d17857 100644
--- a/.github/workflows/run-core-traits-tests.yml
+++ b/.github/workflows/run-core-traits-tests.yml
@@ -11,7 +11,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest, windows-latest]
-        python-version: [3.6, 3.9, 3.10-dev]
+        python-version: ['3.6', '3.7', '3.8', '3.9', '3.10']
 
     runs-on: ${{ matrix.os }}
 
diff --git a/.github/workflows/run-style-checks.yml b/.github/workflows/run-style-checks.yml
index 9b543dcd9..9f6435eff 100644
--- a/.github/workflows/run-style-checks.yml
+++ b/.github/workflows/run-style-checks.yml
@@ -8,7 +8,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest]
-        python-version: [3.6, 3.8]
+        python-version: ['3.8']
 
     runs-on: ${{ matrix.os }}
 
diff --git a/.github/workflows/run-traits-tests.yml b/.github/workflows/run-traits-tests.yml
index a0b656fcd..059f15647 100644
--- a/.github/workflows/run-traits-tests.yml
+++ b/.github/workflows/run-traits-tests.yml
@@ -8,7 +8,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest, windows-latest, macos-latest]
-        python-version: [3.6, 3.7, 3.8, 3.9]
+        python-version: ['3.6', '3.7', '3.8', '3.9', '3.10']
 
     runs-on: ${{ matrix.os }}
 
diff --git a/.github/workflows/test-documentation-build.yml b/.github/workflows/test-documentation-build.yml
index 1986cbc72..1a563b833 100644
--- a/.github/workflows/test-documentation-build.yml
+++ b/.github/workflows/test-documentation-build.yml
@@ -8,7 +8,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest]
-        python-version: [3.6, 3.8]
+        python-version: ['3.8']
 
     runs-on: ${{ matrix.os }}
 
diff --git a/.github/workflows/test-from-pypi.yml b/.github/workflows/test-from-pypi.yml
index 668f8c719..f02f28269 100644
--- a/.github/workflows/test-from-pypi.yml
+++ b/.github/workflows/test-from-pypi.yml
@@ -11,7 +11,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest, windows-latest, macos-latest]
-        python-version: [3.6, 3.7, 3.8, 3.9]
+        python-version: ['3.6', '3.7', '3.8', '3.9', '3.10']
         python-architecture: [x86, x64]
         exclude:
         - os: macos-latest
@@ -58,7 +58,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest, windows-latest, macos-latest]
-        python-version: [3.6, 3.7, 3.8, 3.9]
+        python-version: ['3.6', '3.7', '3.8', '3.9', '3.10']
         python-architecture: [x86, x64]
         exclude:
         - os: macos-latest
diff --git a/setup.py b/setup.py
index 540886200..0b7e4e8cf 100644
--- a/setup.py
+++ b/setup.py
@@ -280,6 +280,7 @@ def get_long_description():
         Programming Language :: Python :: 3.7
         Programming Language :: Python :: 3.8
         Programming Language :: Python :: 3.9
+        Programming Language :: Python :: 3.10
         Programming Language :: Python :: Implementation :: CPython
         Topic :: Scientific/Engineering
         Topic :: Software Development
@@ -308,9 +309,9 @@ def get_long_description():
             "flake8",
             "flake8-ets",
             "mypy",
-            "numpy",
+            "numpy; python_version<'3.10'",
             "pyface",
-            "PySide2",
+            "PySide2; python_version<'3.10'",
             "setuptools",
             "Sphinx>=2.1.0,!=3.2.0",
             "traitsui",