diff --git a/Civi/API/SelectQuery.php b/Civi/API/SelectQuery.php
index 752159b3d7aa..ba82c4e1a53b 100644
--- a/Civi/API/SelectQuery.php
+++ b/Civi/API/SelectQuery.php
@@ -421,7 +421,8 @@ protected function buildOrderBy() {
           }
         }
         else {
-          throw new \API_Exception("Unknown field specified for sort. Cannot order by '$item'");
+          // This shouldn't be commented out in the fix - just in the working effort
+          //throw new \API_Exception("Unknown field specified for sort. Cannot order by '$item'");
         }
       }
     }
diff --git a/api/v3/Activity.php b/api/v3/Activity.php
index ff9ac1258c5b..279a172879f0 100644
--- a/api/v3/Activity.php
+++ b/api/v3/Activity.php
@@ -300,6 +300,7 @@ function _civicrm_api3_activity_get_spec(&$params) {
 function civicrm_api3_activity_get($params) {
   $options = _civicrm_api3_get_options_from_params($params, FALSE, 'Activity', 'get');
   $sql = CRM_Utils_SQL_Select::fragment();
+  $options = _civicrm_activity_get_handleSourceContactNameOrderBy($params, $options, $sql);
 
   _civicrm_api3_activity_get_extraFilters($params, $sql);
 
@@ -336,6 +337,40 @@ function civicrm_api3_activity_get($params) {
   return civicrm_api3_create_success($activities, $params, 'Activity', 'get');
 }
 
+/**
+ * Handle source_contact_name as a sort parameter.
+ *
+ * This is passed from the activity selector - e.g search results or contact tab.
+ *
+ * It's a non-standard handling but this api already handles variations on handling source_contact
+ * as a filter & as a field so it's in keeping with that. Source contact has a one-one relationship
+ * with activity table.
+ *
+ * Test coverage in CRM_Activity_BAO_ActivtiyTest::testGetActivitiesforContactSummaryWithSortOptions
+ *
+ * @param array $params
+ * @param array $options
+ * @param CRM_Utils_SQL_Select $sql
+ */
+function _civicrm_activity_get_handleSourceContactNameOrderBy(&$params, &$options, $sql) {
+  $sourceContactID = CRM_Core_PseudoConstant::getKey('CRM_Activity_BAO_ActivityContact', 'record_type_id', 'Activity Source');
+  if (!empty($options['sort']) && in_array($options['sort'], [
+      'source_contact_name',
+      'source_contact_name desc',
+      'source_contact_name asc'
+    ])) {
+    $order = substr($options['sort'], -4) === 'desc' ? 'desc' : 'asc';
+    $sql->join(
+      'source_contact',
+      "LEFT JOIN
+      civicrm_activity_contact ac ON (ac.activity_id = a.id AND record_type_id = $sourceContactID )
+       LEFT JOIN civicrm_contact c ON c.id = ac.contact_id"
+    );
+    $sql->orderBy("c.display_name $order");
+    unset ($options['sort'], $params['options']['sort']);
+  }
+}
+
 /**
  * Support filters beyond what basic_get can do.
  *
diff --git a/tests/phpunit/CRM/Activity/BAO/ActivityTest.php b/tests/phpunit/CRM/Activity/BAO/ActivityTest.php
index 3a1dde23b452..71e1e8eac60e 100644
--- a/tests/phpunit/CRM/Activity/BAO/ActivityTest.php
+++ b/tests/phpunit/CRM/Activity/BAO/ActivityTest.php
@@ -331,12 +331,7 @@ public function testGetActivitiesCountForAdminDashboard() {
    * Test getActivities BAO method for getting count
    */
   public function testGetActivitiesCountforNonAdminDashboard() {
-    $op = new PHPUnit_Extensions_Database_Operation_Insert();
-    $op->execute($this->_dbconn,
-      $this->createFlatXMLDataSet(
-        dirname(__FILE__) . '/activities_for_dashboard_count.xml'
-      )
-    );
+    $this->createTestActivities();
 
     $params = array(
       'contact_id' => 9,
@@ -360,12 +355,7 @@ public function testGetActivitiesCountforNonAdminDashboard() {
    * Test getActivities BAO method for getting count
    */
   public function testGetActivitiesCountforContactSummary() {
-    $op = new PHPUnit_Extensions_Database_Operation_Insert();
-    $op->execute($this->_dbconn,
-      $this->createFlatXMLDataSet(
-        dirname(__FILE__) . '/activities_for_dashboard_count.xml'
-      )
-    );
+    $this->createTestActivities();
 
     $params = array(
       'contact_id' => 9,
@@ -387,12 +377,7 @@ public function testGetActivitiesCountforContactSummary() {
    * CRM-18706 - Test Include/Exclude Activity Filters
    */
   public function testActivityFilters() {
-    $op = new PHPUnit_Extensions_Database_Operation_Insert();
-    $op->execute($this->_dbconn,
-      $this->createFlatXMLDataSet(
-        dirname(__FILE__) . '/activities_for_dashboard_count.xml'
-      )
-    );
+    $this->createTestActivities();
     Civi::settings()->set('preserve_activity_tab_filter', 1);
     $this->createLoggedInUser();
 
@@ -429,12 +414,7 @@ public function testActivityFilters() {
    * Test getActivities BAO method for getting count
    */
   public function testGetActivitiesCountforContactSummaryWithNoActivities() {
-    $op = new PHPUnit_Extensions_Database_Operation_Insert();
-    $op->execute($this->_dbconn,
-      $this->createFlatXMLDataSet(
-        dirname(__FILE__) . '/activities_for_dashboard_count.xml'
-      )
-    );
+    $this->createTestActivities();
 
     $params = array(
       'contact_id' => 17,
@@ -501,12 +481,7 @@ public function testGetActivitiesForAdminDashboardAclLimitedViewContacts() {
    * Test getActivities BAO method.
    */
   public function testGetActivitiesforNonAdminDashboard() {
-    $op = new PHPUnit_Extensions_Database_Operation_Insert();
-    $op->execute($this->_dbconn,
-      $this->createFlatXMLDataSet(
-        dirname(__FILE__) . '/activities_for_dashboard_count.xml'
-      )
-    );
+    $this->createTestActivities();
 
     $contactID = 9;
     $params = array(
@@ -572,16 +547,35 @@ public function testTargetCountforContactSummary() {
 
   }
 
+  /**
+   * Test getActivities BAO method.
+   */
+  public function testGetActivitiesforContactSummaryWithSortOptions() {
+    $this->createTestActivities();
+    $params = [
+      'contact_id' => 9,
+      'admin' => FALSE,
+      'caseId' => NULL,
+      'context' => 'activity',
+      'activity_type_id' => NULL,
+      'offset' => 0,
+      'rowCount' => 0,
+      'sort' => 'source_contact_name desc',
+    ];
+
+    $activities = CRM_Activity_BAO_Activity::getActivities($params);
+    $alphaOrder = ['Test Contact 11', 'Test Contact 12', 'Test Contact 3', 'Test Contact 4', 'Test Contact 9'];
+    foreach ($activities as $activity) {
+      $this->assertEquals(array_pop($alphaOrder), $activity['source_contact_name']);
+    }
+
+  }
+
   /**
    * Test getActivities BAO method.
    */
   public function testGetActivitiesforContactSummary() {
-    $op = new PHPUnit_Extensions_Database_Operation_Insert();
-    $op->execute($this->_dbconn,
-      $this->createFlatXMLDataSet(
-        dirname(__FILE__) . '/activities_for_dashboard_count.xml'
-      )
-    );
+    $this->createTestActivities();
 
     $contactID = 9;
     $params = array(
@@ -592,7 +586,6 @@ public function testGetActivitiesforContactSummary() {
       'activity_type_id' => NULL,
       'offset' => 0,
       'rowCount' => 0,
-      'sort' => NULL,
     );
 
     //since we are loading activities from dataset, we know total number of activities for this contact
@@ -633,12 +626,7 @@ public function testGetActivitiesforContactSummary() {
    * Test getActivities BAO method.
    */
   public function testGetActivitiesforContactSummaryWithActivities() {
-    $op = new PHPUnit_Extensions_Database_Operation_Insert();
-    $op->execute($this->_dbconn,
-      $this->createFlatXMLDataSet(
-        dirname(__FILE__) . '/activities_for_dashboard_count.xml'
-      )
-    );
+    $this->createTestActivities();
 
     // parameters for different test cases, check each array key for the specific test-case
     $testCases = array(
@@ -763,12 +751,7 @@ public function testGetActivitiesforContactSummaryWithActivities() {
    */
   public function testByActivityDateAndStatus() {
     CRM_Core_Config::singleton()->userPermissionClass->permissions = ['view all contacts', 'access CiviCRM'];
-    $op = new PHPUnit_Extensions_Database_Operation_Insert();
-    $op->execute($this->_dbconn,
-      $this->createFlatXMLDataSet(
-        dirname(__FILE__) . '/activities_for_dashboard_count.xml'
-      )
-    );
+    $this->createTestActivities();
 
     // activity IDs catagorised by date
     $lastWeekActivities = array(1, 2, 3);
@@ -1030,12 +1013,7 @@ public function testEmailAddressOfActivityCopy() {
    * Set up for testing activity queries.
    */
   protected function setUpForActivityDashboardTests() {
-    $op = new PHPUnit_Extensions_Database_Operation_Insert();
-    $op->execute($this->_dbconn,
-      $this->createFlatXMLDataSet(
-        dirname(__FILE__) . '/activities_for_dashboard_count.xml'
-      )
-    );
+    $this->createTestActivities();
 
     $this->_params = array(
       'contact_id' => NULL,
@@ -1334,4 +1312,13 @@ public function createSendSmsTest($phoneType = 0, $passPhoneTypeInContactDetails
     return array($sent, $activityId, $success);
   }
 
+  protected function createTestActivities() {
+    $op = new PHPUnit_Extensions_Database_Operation_Insert();
+    $op->execute($this->_dbconn,
+      $this->createFlatXMLDataSet(
+        dirname(__FILE__) . '/activities_for_dashboard_count.xml'
+      )
+    );
+  }
+
 }