diff --git a/README.md b/README.md
index 456f6ab4..33c2cb23 100644
--- a/README.md
+++ b/README.md
@@ -20,6 +20,13 @@ cd pycloudlib
 uv sync
 ```
 
+## Supported platforms
+
+pycloudlib runs on **Linux only**, tested on Ubuntu 24.04 LTS (Python 3.12) and
+Ubuntu 26.04 LTS (Python 3.14). See the
+[supported platforms](https://pycloudlib.readthedocs.io/en/latest/supported_platforms.html)
+documentation for the full support matrix and policy details.
+
 ## Usage
 
 The library exports each cloud with a standard set of functions for operating on instances, snapshots, and images. There are also cloud specific operations that allow additional operations.
diff --git a/VERSION b/VERSION
index 7db421b5..c18b4581 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-1!11.1.2
+1!12.0.1
diff --git a/docs/index.rst b/docs/index.rst
index 9b2e2040..294b6eb3 100644
--- a/docs/index.rst
+++ b/docs/index.rst
@@ -79,6 +79,7 @@ use the pycloudlib-devs@lists.launchpad.net list.
    ssh_keys
    images
    resource_cleanup
+   supported_platforms
 
 .. toctree::
    :hidden:
diff --git a/docs/supported_platforms.md b/docs/supported_platforms.md
new file mode 100644
index 00000000..ab0d17c4
--- /dev/null
+++ b/docs/supported_platforms.md
@@ -0,0 +1,35 @@
+# Supported platforms
+
+This page documents the operating systems and Python versions that pycloudlib
+is supported and tested on.
+
+## Host operating system
+
+pycloudlib runs on **Linux only**.
+
+### Support matrix
+
+The version of python supported will track the versions of python included in the [two most-recent Ubuntu LTS releases](https://ubuntu.com/about/release-cycle).
+
+ The current Host Operating system and python support matrix represets the tested host environments:
+
+| Host OS             | Native Python | CI runner        | Tox env  |
+|---------------------|---------------|------------------|----------|
+| Ubuntu 24.04 LTS    | 3.12          | `ubuntu-24.04`   | `py312`  |
+| Ubuntu 26.04 LTS    | 3.14          | `ubuntu-26.04`*  | `py314`* |
+
+### Notes
+
+* Other Linux distributions *may* work but are not tested. Bugs reported
+  against untested distributions will be considered on a best-effort basis.
+* Windows and macOS are not supported.
+* Integration tests have Linux-only hard requirements that prevent the host
+  OS matrix from extending beyond Linux:
+  * the **LXD snap** (installed via the `canonical/setup-lxd` action in
+    `.github/workflows/ci.yaml`), and
+  * the **`distro-info`** apt package.
+
+## Python versions
+
+pycloudlib's documented and tested minimum Python version is **3.12**, the
+native Python of the oldest in-scope Ubuntu LTS release (24.04).