diff --git a/lib/PayPal/Rest/ApiContext.php b/lib/PayPal/Rest/ApiContext.php
index dd68fe8..25bca9b 100644
--- a/lib/PayPal/Rest/ApiContext.php
+++ b/lib/PayPal/Rest/ApiContext.php
@@ -85,13 +85,19 @@ class ApiContext
      */
     public function getRequestId()
     {
-        if ($this->requestId == null) {
-            $this->requestId = $this->generateRequestId();
-        }
-
         return $this->requestId;
     }
 
+    /**
+     * Sets the request ID
+     *
+     * @param string $requestId the PayPal-Request-Id value to use
+     */
+    public function setRequestId($requestId)
+    {
+        $this->requestId = $requestId;
+    }
+
     /**
      * Resets the requestId that can be used to set the PayPal-request-id
      * header used for idempotency. In cases where you need to make multiple create calls
diff --git a/tests/PayPal/Test/Rest/ApiContextTest.php b/tests/PayPal/Test/Rest/ApiContextTest.php
index 32c711c..9869b9d 100644
--- a/tests/PayPal/Test/Rest/ApiContextTest.php
+++ b/tests/PayPal/Test/Rest/ApiContextTest.php
@@ -22,13 +22,27 @@ class ApiContextTest extends PHPUnit_Framework_TestCase
     public function testGetRequestId()
     {
         $requestId = $this->apiContext->getRequestId();
-        $this->assertNotNull($requestId);
-        $this->assertEquals($requestId, $this->apiContext->getRequestId());
+        $this->assertNull($requestId);
+    }
+
+    public function testSetRequestId()
+    {
+        $this->assertNull($this->apiContext->getRequestId());
+
+        $expectedRequestId = 'random-value';
+        $this->apiContext->setRequestId($expectedRequestId);
+        $requestId = $this->apiContext->getRequestId();
+        $this->assertEquals($expectedRequestId, $requestId);
     }
 
     public function testResetRequestId()
     {
-        $requestId = $this->apiContext->getRequestId();
+        $this->assertNull($this->apiContext->getRequestId());
+
+        $requestId = $this->apiContext->resetRequestId();
+        $this->assertNotNull($requestId);
+
+        // Tests that another resetRequestId call will generate a new ID
         $newRequestId = $this->apiContext->resetRequestId();
         $this->assertNotNull($newRequestId);
         $this->assertNotEquals($newRequestId, $requestId);