diff --git a/addthis.install b/addthis.install
index 9fe65f5619aa0e56afcb2d25410583d27c195e97..7cd8b8eaf53f016dbc44580af90db0e45848c333 100644
--- a/addthis.install
+++ b/addthis.install
@@ -31,6 +31,7 @@ function addthis_field_schema($field) {
  * Implements hook_uninstall().
  */
 function addthis_uninstall() {
+  variable_del(AddThis::ADDRESSBOOK_ENABLED_KEY);
   variable_del(AddThis::BLOCK_WIDGET_TYPE_KEY);
   variable_del(AddThis::BOOKMARK_URL_KEY);
   variable_del(AddThis::CLICKBACK_TRACKING_ENABLED_KEY);
diff --git a/addthis.test b/addthis.test
index d84e0d6755a97270d8bfe19d50dd2286722af602..9001d661ba364c6f4eddc071c8b82afcff06ac09 100644
--- a/addthis.test
+++ b/addthis.test
@@ -161,6 +161,8 @@ class AddThisFunctionalityTestCase extends DrupalWebTestCase {
 
     $edit[AddThis::CLICKBACK_TRACKING_ENABLED_KEY] = TRUE;
 
+    $edit[AddThis::ADDRESSBOOK_ENABLED_KEY] = TRUE;
+
     $numberOfPreferredServices = 5;
     $edit[AddThis::NUMBER_OF_PREFERRED_SERVICES_KEY] = $numberOfPreferredServices;
 
@@ -194,7 +196,7 @@ class AddThisFunctionalityTestCase extends DrupalWebTestCase {
 
     $this->addThis508CompliantSettingShouldBeAbleToBeSaved();
 
-    $this->addThisClickbackTrackingSettingShouldBeAbleToBeSaved();
+    $this->addThisClickbackTrackingEnabledSettingShouldBeAbleToBeSaved();
 
     $this->addThisNumberOfPreferredServicesShouldBeAbleToBeSaved($numberOfPreferredServices);
 
@@ -232,9 +234,14 @@ class AddThisFunctionalityTestCase extends DrupalWebTestCase {
                               'AddThis 508 compliant setting should be able to be saved.');
   }
 
-  private function addThisClickbackTrackingSettingShouldBeAbleToBeSaved() {
+  private function addThisClickbackTrackingEnabledSettingShouldBeAbleToBeSaved() {
     $this->assertFieldChecked('edit-addthis-clickback-tracking-enabled',
-                              'AddThis clickback tracking setting should be able to be saved.');
+                              'AddThis clickback tracking enabled setting should be able to be saved.');
+  }
+
+  private function addThisAddressbookEnabledSettingShouldBeAbleToBeSaved() {
+    $this->assertFieldChecked('edit-addthis-addressbook-enabled',
+                              'AddThis addressbook enabled setting should be able to be saved.');
   }
 
   private function addThisNumberOfPreferredServicesShouldBeAbleToBeSaved($numberOfPreferredServices) {
diff --git a/classes/AddThis.php b/classes/AddThis.php
index 2a7317294a5b5d05499d63a590bf7a238cb14cea..7bdd981501b1ffc43c28618cbfc06a79bbec4389 100644
--- a/classes/AddThis.php
+++ b/classes/AddThis.php
@@ -24,6 +24,7 @@ class AddThis {
   const TITLE_ATTRIBUTE = 'addthis:title';
 
   // Persistent variable keys
+  const ADDRESSBOOK_ENABLED_KEY = 'addthis_addressbook_enabled';
   const BLOCK_WIDGET_TYPE_KEY = 'addthis_block_widget_type';
   const BOOKMARK_URL_KEY = 'addthis_bookmark_url';
   const CLICKBACK_TRACKING_ENABLED_KEY = 'addthis_clickback_tracking_enabled';
@@ -172,6 +173,7 @@ class AddThis {
         . $this->addThisConfigurationGenerator->generate('ui_cobrand', $this->getCoBrand())
         . $this->addThisConfigurationGenerator->generate('ui_508_compliant', $this->get508Compliant())
         . $this->addThisConfigurationGenerator->generate('data_track_clickback', $this->isClickbackTrackingEnabled())
+        . $this->addThisConfigurationGenerator->generate('ui_use_addressbook', $this->isAddressbookEnabled())
         . '}'
       ;
     }
@@ -222,6 +224,10 @@ class AddThis {
     return variable_get(self::CLICKBACK_TRACKING_ENABLED_KEY, FALSE);
   }
 
+  public function isAddressbookEnabled() {
+    return variable_get(self::ADDRESSBOOK_ENABLED_KEY, FALSE);
+  }
+
   private function getLargeButtonWidgetMarkup($entity) {
     return '<a class="addthis_button" '
            . $this->getAddThisAttributesMarkup($entity)
diff --git a/includes/addthis.admin.inc b/includes/addthis.admin.inc
index 01ef3bfa6789e9ebb34c79a3c423383078092541..bfad353aa8d75400b756d513212b3e517f08e3dc 100644
--- a/includes/addthis.admin.inc
+++ b/includes/addthis.admin.inc
@@ -70,7 +70,6 @@ function addthis_admin_settings_form($form_state) {
     '#default_value' => AddThis::getInstance()->get508Compliant(),
     '#required' => FALSE,
   );
-
   $form['data_tracking_fieldset'] = array(
     '#type' => 'fieldset',
     '#title' => t('Data tracking'),
@@ -84,6 +83,19 @@ function addthis_admin_settings_form($form_state) {
     '#default_value' => AddThis::getInstance()->isClickbackTrackingEnabled(),
     '#required' => FALSE,
   );
+  $form['email_settings_fieldset'] = array(
+    '#type' => 'fieldset',
+    '#title' => t('Email settings'),
+    '#collapsible' => TRUE,
+    '#collapsed' => TRUE,
+  );
+  $form['email_settings_fieldset'][AddThis::ADDRESSBOOK_ENABLED_KEY] = array(
+    '#type' => 'checkbox',
+    '#title' => t('Use addressbook'),
+    '#description' => 'If checked, the user will be able import their contacts from popular webmail services when using AddThis\'s email sharing.',
+    '#default_value' => AddThis::getInstance()->isAddressbookEnabled(),
+    '#required' => FALSE,
+  );
   $form['service_urls_fieldset'] = array(
     '#type' => 'fieldset',
     '#title' => t('Service URLs'),