diff --git a/Dockerfile b/Dockerfile
index b4cad03..85e5e16 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -21,9 +21,12 @@ RUN set -x && \
     gosu nobody true && \
     apt-get clean && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
 
-RUN pyenv local 3.7.5 && \
+ENV TOX_PYTHON_VERSION 3.9.1
+ENV TOX_VERSION 3.21.2
+
+RUN pyenv local $TOX_PYTHON_VERSION && \
     python -m pip install -U pip && \
-    python -m pip install tox==3.14.0 && \
+    python -m pip install tox==$TOX_VERSION && \
     pyenv local --unset && \
     pyenv rehash
 
diff --git a/README.md b/README.md
index dea4d22..307cdcd 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,7 @@
 # Tox-Base
 
-This image contains Python versions 2.6, 2.7, 3.4, 3.5, 3.6, 3.7, 3.8, PyPy, and PyPy3.
+This image contains
+  - Python versions 2.6, 2.7, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9
+  - PyPy versions 2.7, 3.6, 3.7
+
 It also includes [tox](https://pypi.python.org/pypi/tox) for running test automation against the various versions.
diff --git a/python-versions.txt b/python-versions.txt
index f075034..4fc859d 100644
--- a/python-versions.txt
+++ b/python-versions.txt
@@ -1,11 +1,13 @@
-3.8.0
-3.7.5
-3.6.9
-3.5.7
+3.9.1
+3.8.7
+3.7.9
+3.6.12
+3.5.9
 3.4.10
 3.3.7
-2.7.17
+2.7.18
 2.6.9
-pypy2.7-7.2.0
-pypy3.6-7.2.0
-pypy3.3-5.5-alpha
+
+pypy3.7-7.3.3
+pypy3.6-7.3.3
+pypy2.7-7.3.3