diff --git a/README.md b/README.md
index 699ff54..5a85115 100644
--- a/README.md
+++ b/README.md
@@ -5,7 +5,7 @@
 ## Usage
 
 ``` yaml
-- uses: tesseract-robotics/colcon-action@v8
+- uses: tesseract-robotics/colcon-action@v9
   with:
     # Script that runs before anything else in build steps (optional, default: '')
     before-script: ''
@@ -17,6 +17,10 @@
     rosdep-enabled: 'true'
     # Additional args to pass to rosdep install (optional, default: '-r')
     rosdep-install-args: '-r'
+    # Indicate if ROS PPA should be added (optional, default: 'false').
+    # The ROS PPA must be added if the Linux OS on which this action runs does not already contain a ROS distro.
+    # The ROS PPA should not be added if the Linux OS already contains a ROS distro (e.g., ROS Docker image)
+    add-ros-ppa: 'false'
     # The relative path to the vcs repos file (optional, default: '')
     vcs-file: 'dependencies.repos'
     # Additional args to pass to colcon build for upstream workspace (optional, default: '')
diff --git a/action.yml b/action.yml
index 551cda2..90b135f 100644
--- a/action.yml
+++ b/action.yml
@@ -21,6 +21,10 @@ inputs:
     description: "Additional args to pass to rosdep install (optional)"
     required: false
     default: '-r'
+  add-ros-ppa:
+    description: "Indicate if ROS PPA should be added (optional)"
+    required: false
+    default: 'true'
   vcs-file:
     description: "The relative path to the vcs repos file (optional)"
     required: false
@@ -65,7 +69,7 @@ runs:
         python3 -m pip install ninja -q
 
     - name: Install ROS/Colcon PPA (Linux)
-      if: runner.os == 'Linux'
+      if: inputs.add-ros-ppa == 'true' && runner.os == 'Linux'
       shell: bash
       run: |
         curl -sSL https://raw.githubusercontent.com/ros/rosdistro/master/ros.key -o /usr/share/keyrings/ros-archive-keyring.gpg