diff --git a/modules/field_ui/field_ui.admin.inc b/modules/field_ui/field_ui.admin.inc
index 44770ac..ad966f8 100644
--- a/modules/field_ui/field_ui.admin.inc
+++ b/modules/field_ui/field_ui.admin.inc
@@ -1051,6 +1051,16 @@ function field_ui_display_overview_form($form, &$form_state, $entity_type, $bund
         $settings_form = $function($field, $instance, $view_mode, $form, $form_state);
       }
 
+      // Allow other modules to alter the formater settings form.
+      $context = array(
+        'module' => $formatter['module'],
+        'formatter' => $formatter,
+        'field' => $field,
+        'instance' => $instance,
+        'view_mode' => $view_mode,
+        'form' => $form,
+      );
+      drupal_alter('field_formatter_settings_form', $settings_form, $form_state, $context);
       if ($settings_form) {
         $table[$name]['format']['#cell_attributes'] = array('colspan' => 3);
         $table[$name]['format']['settings_edit_form'] = array(
@@ -1086,6 +1096,12 @@ function field_ui_display_overview_form($form, &$form_state, $entity_type, $bund
     else {
       // Display a summary of the current formatter settings.
       $summary = module_invoke($formatter['module'], 'field_formatter_settings_summary', $field, $instance, $view_mode);
+      $context = array(
+        'field' => $field,
+        'instance' => $instance,
+        'view_mode' => $view_mode,
+      );
+      drupal_alter('field_formatter_settings_summary', $summary, $context);
       $table[$name]['settings_summary'] = array();
       $table[$name]['settings_edit'] = array();
       if ($summary) {
diff --git a/modules/field_ui/field_ui.api.php b/modules/field_ui/field_ui.api.php
index 05d9f05..57ef9d6 100644
--- a/modules/field_ui/field_ui.api.php
+++ b/modules/field_ui/field_ui.api.php
@@ -170,6 +170,41 @@ function hook_field_formatter_settings_form($field, $instance, $view_mode, $form
 }
 
 /**
+ * Alter the formatter settings form.
+ *
+ * @param $element
+ *   Form array as returned by hook_field_formatter_settings_form().
+ * @param $form_state
+ *   The form state of the (entire) configuration form.
+ * @param $context
+ *   An associative array with the following elements:
+ *   - 'module': The module that contains the definition of this formatter.
+ *   - 'formatter': The formatter type description array.
+ *   - 'field': The field structure being configured.
+ *   - 'instance': The instance structure being configured.
+ *   - 'view_mode': The view mode being configured.
+ *   - 'form': The (entire) configuration form array.
+ */
+function hook_field_formatter_settings_form_alter(&$settings_form, &$form_state, $context) {
+
+}
+
+/**
+ * Alter the field formatter settings summary.
+ *
+ * @param $summary
+ *   The summary as returned by hook_field_formatter_settings_summary().
+ * @param $context
+ *   An associative array with the following elements:
+ *   - 'field': The field structure being configured.
+ *   - 'instance': The instance structure being configured.
+ *   - 'view_mode': The view mode being configured.
+ */
+function hook_field_formatter_settings_summary_alter(&$sumary, $context) {
+
+}
+
+/**
  * Return a short summary for the current formatter settings of an instance.
  *
  * If an empty result is returned, the formatter is assumed to have no