diff --git a/README.md b/README.md
index 18bd7ffb..ca93b653 100644
--- a/README.md
+++ b/README.md
@@ -258,10 +258,7 @@ $ pmbootstrap stats --arch=armhf
 
 ### Use alternative sudo
 
-pmbootstrap supports `doas` and `sudo`.
-If multiple sudo implementations are installed, pmbootstrap will use `doas`.
-You can set the `PMB_SUDO` environmental variable to define the sudo
-implementation you want to use.
+See `PMB_SUDO` in `docs/environment_variables.md`.
 
 ### Select SSH keys to include and make authorized in new images
 
diff --git a/docs/environment_variables.md b/docs/environment_variables.md
new file mode 100644
index 00000000..51baa9fe
--- /dev/null
+++ b/docs/environment_variables.md
@@ -0,0 +1,7 @@
+# Environment Variables
+
+## `PMB_SUDO`
+
+pmbootstrap supports `doas` and `sudo`. If multiple sudo implementations are
+installed, pmbootstrap will use `doas`. You can set the `PMB_SUDO`
+environmental variable to define the sudo implementation you want to use.
diff --git a/docs/index.rst b/docs/index.rst
index ab6cb80b..a9cede2a 100644
--- a/docs/index.rst
+++ b/docs/index.rst
@@ -23,6 +23,7 @@ For further information, please check out the `postmarketOS-wiki`_.
    ssh-keys
    api/modules
    mirrors
+   environment_variables