diff --git a/README.md b/README.md
index 3c018f9..502a6ff 100644
--- a/README.md
+++ b/README.md
@@ -43,6 +43,7 @@ Adding subscriptions requires a List ID and an email, but there are a few other
 * name
 * array of custom fields (eg `{age: 22}`)
 * boolean for whether to resubscribe addresses that have previously been removed (default true)
+* whether the subscriber has given permission to have their email opens and clicks tracked. Values: 'Yes', 'No' or 'Unchanged' (default)
 
 Note about the **list ID**: this is _not_ the parameter "listID" in the URL when viewing a list. Annoyingly, Campaign Monitor uses two IDs for lists. To find your List ID, view [this FAQ](https://createform.com/support/campaignmonitor-list).
 
@@ -65,6 +66,8 @@ The easiest way to add subscribers is by posting a form with their data. This fo
   <!-- optional fields -->
   <input type="hidden" name="resubscribe" value="0" /><!-- don't resubscribe if email has already opted out -->
 
+  <input type="hidden" name="consenttotrack" value="yes" /><!-- Tracking is permitted for this email address -->
+
   <label for="name">Name</label>
   <input type="text" id="name" name="name" />
 
@@ -100,7 +103,8 @@ Add additional parameters as needed:
 {% set name = 'Steve' %}
 {% set customFields = {age: 22, city: 'Chicago'} %}
 {% set resubscribe = false %}
-{% craft.oneCampaignMonitor.subscribe(listId, email, name, customFields, resubscribe) %}
+{% set consenttotrack = 'Yes' %}
+{% craft.oneCampaignMonitor.subscribe(listId, email, name, customFields, resubscribe, consenttotrack) %}
 ```
 
 ### Service (in controllers, etc)
diff --git a/controllers/OneCampaignMonitor_SubscribersController.php b/controllers/OneCampaignMonitor_SubscribersController.php
index 9fe10d5..82828e6 100644
--- a/controllers/OneCampaignMonitor_SubscribersController.php
+++ b/controllers/OneCampaignMonitor_SubscribersController.php
@@ -16,10 +16,11 @@ public function actionAdd() {
         $name   = craft()->request->getParam('name') ?: '';
         $customFields = craft()->request->getParam('customFields') ?: array();
         $resubscribe = craft()->request->getParam('resubscribe') ?: true;
+        $consenttotrack = craft()->request->getParam('consenttotrack') ?: 'Unchanged';
 
         $error = null;
         try {
-            craft()->oneCampaignMonitor_subscribers->add($listId, $email, $name, $customFields, $resubscribe);
+            craft()->oneCampaignMonitor_subscribers->add($listId, $email, $name, $customFields, $resubscribe, $consenttotrack);
         } catch (Exception $e) {
             OneCampaignMonitorPlugin::log($e->getMessage(), LogLevel::Error);
             $error = $e->getMessage();
diff --git a/services/OneCampaignMonitor_SubscribersService.php b/services/OneCampaignMonitor_SubscribersService.php
index 66fa8f5..382f818 100644
--- a/services/OneCampaignMonitor_SubscribersService.php
+++ b/services/OneCampaignMonitor_SubscribersService.php
@@ -15,7 +15,7 @@ class OneCampaignMonitor_SubscribersService extends OneCampaignMonitor_BaseServi
      * @param  $merge
      * @throws Exception
      */
-    public function add($listId, $email, $name=null, $customFields=array(), $resubscribe=true) {
+    public function add($listId, $email, $name=null, $customFields=array(), $resubscribe=true, $consenttotrack='Unchanged') {
         if (!$listId) {
             throw new Exception('List ID is required');
         }
@@ -28,7 +28,8 @@ public function add($listId, $email, $name=null, $customFields=array(), $resubsc
             'EmailAddress' => $email,
             'Name' => $name,
             'CustomFields' => $this->parseCustomFields($customFields),
-            'Resubscribe' => $resubscribe
+            'Resubscribe' => $resubscribe,
+            'ConsentToTrack' => $consenttotrack
         ]);
 
         $error = null;
@@ -57,7 +58,7 @@ public function exists($listId, $email) {
         $connection = new \CS_REST_Subscribers($listId, $this->auth());
 
         $result = $connection->get($email);
-            
+
         $error = null;
         return $this->response($result, $error);
     }
@@ -81,7 +82,7 @@ public function update($listId, $email, $name=null, $customFields=array(), $resu
         }
 
         $connection = new \CS_REST_Subscribers($listId, $this->auth());
-        
+
         $subscriber = [
             'Resubscribe' => $resubscribe
         ];
@@ -94,7 +95,7 @@ public function update($listId, $email, $name=null, $customFields=array(), $resu
 
         if ($mergeMultiFields) {
             $result = $connection->get($email);
-            
+
             $error = null;
             if (!$this->response($result, $error)) {
                 throw new Exception($error);
@@ -132,11 +133,11 @@ public function addOrUpdate($listId, $email, $name=null, $customFields=array(),
         if (!empty($customFields)) {
             craft()->oneCampaignMonitor_lists->ensureCustomFieldsExist($listId, $customFields);
         }
-        
+
         if ($this->exists($listId, $email)) {
             return $this->update($listId, $email, $name, $customFields, $resubscribe, $mergeMultiFields);
         } else {
             return $this->add($listId, $email, $name, $customFields);
-        }  
+        }
     }
 }
diff --git a/variables/OneCampaignMonitorVariable.php b/variables/OneCampaignMonitorVariable.php
index 3ea587c..b67913a 100644
--- a/variables/OneCampaignMonitorVariable.php
+++ b/variables/OneCampaignMonitorVariable.php
@@ -2,8 +2,8 @@
 namespace Craft;
 
 class OneCampaignMonitorVariable {
-    public function subscribe($list_id, $email, $name=null, $customFields=array(), $resubscribe=true) {
-        return craft()->oneCampaignMonitor_subscribers->add($list_id, $email, $name, $customFields, $resubscribe);
+    public function subscribe($list_id, $email, $name=null, $customFields=array(), $resubscribe=true, $consenttotrack='Unchanged') {
+        return craft()->oneCampaignMonitor_subscribers->add($list_id, $email, $name, $customFields, $resubscribe, $consenttotrack);
     }
 
     public function hasSubscribed($listId) {