diff --git a/commerce_pdm.install b/commerce_pdm.install
index e69de29..f8439f3 100644
--- a/commerce_pdm.install
+++ b/commerce_pdm.install
@@ -0,0 +1,16 @@
+<?php
+
+/**
+ * @file
+ * Commerce PDM installation functions.
+ */
+
+/**
+ * Implements hook_uninstall().
+ */
+function commerce_pdm_uninstall() {
+  // Delete variables stored by Commerce PDM.
+  db_delete('variable')
+    ->condition('name', db_like('commerce_pdm_') . '%', 'LIKE')
+    ->execute();
+}