diff --git a/captcha.module b/captcha.module
index 645da61..2949cae 100644
--- a/captcha.module
+++ b/captcha.module
@@ -383,6 +383,10 @@ function theme_captcha($variables) {
  */
 function captcha_form_alter(&$form, &$form_state, $form_id) {
 
+  if (variable_get('disable_captcha', FALSE)) {
+    return;
+  }
+
   if (!user_access('skip CAPTCHA')) {
     // Visitor does not have permission to skip CAPTCHAs.
     module_load_include('inc', 'captcha');