diff --git a/src/TwitterAds.php b/src/TwitterAds.php
index da8cf4e..3ecdd32 100644
--- a/src/TwitterAds.php
+++ b/src/TwitterAds.php
@@ -20,7 +20,7 @@
  */
 class TwitterAds extends Config
 {
-    const API_VERSION      = '10';
+    const API_VERSION      = '11';
     const API_REST_VERSION = '1.1';
     const API_HOST = 'https://ads-api.twitter.com';
     const API_HOST_SANDBOX = 'https://ads-api-sandbox.twitter.com';
diff --git a/src/TwitterAds/Campaign/Campaign.php b/src/TwitterAds/Campaign/Campaign.php
index b10eaa1..df22c7d 100644
--- a/src/TwitterAds/Campaign/Campaign.php
+++ b/src/TwitterAds/Campaign/Campaign.php
@@ -31,6 +31,7 @@ class Campaign extends Analytics
     protected $properties = [
         CampaignFields::NAME,
         CampaignFields::FUNDING_INSTRUMENT_ID,
+        CampaignFields::BUDGET_OPTIMIZATION,
         CampaignFields::START_TIME,
         CampaignFields::END_TIME,
         CampaignFields::ENTITY_STATUS,
@@ -51,6 +52,7 @@ class Campaign extends Analytics
     protected $daily_budget_amount_local_micro;
     protected $total_budget_amount_local_micro;
     protected $duration_in_days;
+    protected $budget_optimization;
     protected $frequency_cap;
 
     /**
@@ -252,6 +254,22 @@ public function setStandardDelivery($standard_delivery)
         $this->standard_delivery = $standard_delivery;
     }
 
+    /**
+     * @return mixed
+     */
+    public function getBudgetOptimization()
+    {
+        return $this->budget_optimization;
+    }
+
+    /**
+     * @param mixed $budget_optimization
+     */
+    public function setBudgetOptimization($budget_optimization)
+    {
+        $this->budget_optimization = $budget_optimization;
+    }
+
     /**
      * @return mixed
      */
diff --git a/src/TwitterAds/Fields/CampaignFields.php b/src/TwitterAds/Fields/CampaignFields.php
index 591ce8b..839bf1d 100644
--- a/src/TwitterAds/Fields/CampaignFields.php
+++ b/src/TwitterAds/Fields/CampaignFields.php
@@ -30,8 +30,8 @@ class CampaignFields extends Fields
     const ENTITY_STATUS                   = 'entity_status';
     const WITH_TOTAL_COUNT                = 'with_total_count';
     const WITH_DRAFT                      = 'with_draft';
-
-    const ACCOUNT_ID = 'account_id';
+    const BUDGET_OPTIMIZATION             = 'budget_optimization';
+    const ACCOUNT_ID                      = 'account_id';
     const CAMPAIGN_IDS                    = 'campaign_ids';
     const FUNDING_INSTRUMENT_IDS          = 'funding_instrument_ids';
 }