diff --git a/rolereference.module b/rolereference.module
index 6cf179a..2cfa64a 100755
--- a/rolereference.module
+++ b/rolereference.module
@@ -49,6 +49,7 @@ function rolereference_field_settings_form($field, $instance, $has_data) {
   $form['referenceable_roles'] = array(
     '#type'          => 'checkboxes',
     '#title'         => t('Roles that can be referenced'),
+    '#description'   => t('Select roles that may be referenced by this field. All roles will be available if none are checked.'),
     '#multiple'      => TRUE,
     '#default_value' => is_array($settings['referenceable_roles'])
       ? $settings['referenceable_roles']
@@ -248,6 +249,9 @@ function rolereference_potential_references($referenceable_roles) {
         $roles[$rid] = $user_roles[$rid];
       }
     }
+    if (empty($roles)) {
+      $roles = $user_roles;
+    }
   }
   return $roles;
-}
\ No newline at end of file
+}