diff --git a/website/_includes/special-keys.md b/website/_includes/special-keys.md
new file mode 100644
index 000000000..ec5d59f9c
--- /dev/null
+++ b/website/_includes/special-keys.md
@@ -0,0 +1,9 @@
+Aider has special support for providing
+OpenAI and Anthropic API keys
+via command line switches and yaml config settings.
+*All other LLM providers* must 
+have their keys and settings 
+specified in environment variables.
+This can be done in your shell, 
+or by using a 
+[`.env` file](/docs/dotenv.html).
diff --git a/website/docs/llms/azure.md b/website/docs/llms/azure.md
index ada2beb8d..55aa791f4 100644
--- a/website/docs/llms/azure.md
+++ b/website/docs/llms/azure.md
@@ -25,3 +25,6 @@ aider --model azure/<your_deployment_name>
 # List models available from Azure
 aider --models azure/
 ```
+
+Note that aider will also use environment variables
+like `AZURE_OPENAI_API_xxx`.