diff --git a/flagging_form.module b/flagging_form.module
index e776ea7..099d2c9 100644
--- a/flagging_form.module
+++ b/flagging_form.module
@@ -172,14 +172,16 @@ function flagging_form_form_flag_form_alter(&$form) {
   foreach (flagging_form_interactions() as $interaction => $info) {
     $interactions[$interaction] = $info['title'] . ' <div class="description">' . $info['description'] . '</div>';
   }
-  $settings['form_interaction'] = array(
-    '#type' => 'radios',
-    '#title' => t('Forms interaction'),
-    '#options' => $interactions,
-    '#default_value' => isset($flag->form_interaction) && isset($interactions[$flag->form_interaction]) ? $flag->form_interaction : 'default',
-    '#description' => t('How users are to interact with the forms. Additional interaction modes are available by installing additional modules.'),
-    '#access' => empty($flag->locked['form_interaction']),
-  );
+  if (!empty($interactions)) {
+    $settings['form_interaction'] = array(
+      '#type' => 'radios',
+      '#title' => t('Forms interaction'),
+      '#options' => $interactions,
+      '#default_value' => isset($flag->form_interaction) && isset($interactions[$flag->form_interaction]) ? $flag->form_interaction : 'default',
+      '#description' => t('How users are to interact with the forms. Additional interaction modes are available by installing additional modules.'),
+      '#access' => empty($flag->locked['form_interaction']),
+    );
+  }
 
   $form['display']['link_options_form'] = $settings;
 }