diff --git a/classes/studyplanservice.php b/classes/studyplanservice.php
index 8046861..347e116 100644
--- a/classes/studyplanservice.php
+++ b/classes/studyplanservice.php
@@ -894,6 +894,63 @@ class studyplanservice extends \external_api {
 
     }
 
+    /****************************************
+     *                                      *
+     * mark/unmark competency required      *
+     *                                      *
+     ****************************************/
+
+    /**
+     * Parameter description for webservice function include_grade
+     */
+    public static function require_competency_parameters() : \external_function_parameters {
+        return new \external_function_parameters( [
+            "competency_id" => new \external_value(PARAM_INT, 'id of competency '),
+            "item_id" => new \external_value(PARAM_INT, 'id of studyitem '),
+            "required" => new \external_value(PARAM_BOOL, 'required grade or not', VALUE_DEFAULT),
+            ] );
+    }
+
+    /**
+     * Return value description for webservice function include_grade
+     */
+    public static function require_competency_returns() : \external_description {
+        return success::structure();
+    }
+
+
+    /**
+     * Mark a gradable item for inclusion in the studyplan
+     * @param mixed $gradeid Id of gradable
+     * @param mixed $itemid Id of study item
+     * @param bool $include Include grade or not
+     * @param bool $required Mark grade as required or not
+     * @return array Success/Fail model
+     *
+     */
+    public static function require_competency($competencyid, $itemid, $include, $required = false) {
+        global $USER;
+        $item = studyitem::find_by_id($itemid);
+        // Find related course and course context.
+        if($item->courseid()) {
+            $coursecontext = \context_course::instance($item->courseid());
+            // Do sanity checks.
+            \external_api::validate_context($coursecontext);
+        } else {
+            $coursecontext = null;
+            \external_api::validate_context($item->context());
+        }
+
+        // Check correct capabilities.
+        if (has_capability('local/treestudyplan:editstudyplan', $item->context()) ||
+           ($coursecontext && is_enrolled($coursecontext, $USER, 'local/treestudyplan:selectowngradables'))) {
+           return coursecompetencyinfo::require_competency($competencyid, $itemid, $include, $required)->model();
+        } else {
+            return success::fail("Access denied")->model();
+        }
+
+    }
+
     /****************************
      *                          *
      * list aggregators         *
diff --git a/db/services.php b/db/services.php
index c30bf44..820093c 100644
--- a/db/services.php
+++ b/db/services.php
@@ -322,6 +322,15 @@ $functions = [
         'capabilities'  => 'local/treestudyplan:editstudyplan, local/treestudyplan:selectowngradables',
         'loginrequired' => true,
     ],
+    'local_treestudyplan_require_competency' => [         // Web service function name.
+        'classname'     => '\local_treestudyplan\studyplanservice',  // Class containing the external function.
+        'methodname'    => 'require_competency',          // External function name.
+        'description'   => 'Mark competency as required in course outcome',
+        'type'          => 'read',                  // Database rights of the web service function (read, write).
+        'ajax'          => true,
+        'capabilities'  => 'local/treestudyplan:editstudyplan, local/treestudyplan:selectowngradables',
+        'loginrequired' => true,
+    ],
     'local_treestudyplan_all_associated' => [         // Web service function name.
         'classname'     => '\local_treestudyplan\associationservice',  // Class containing the external function.
         'methodname'    => 'all_associated',          // External function name.
diff --git a/version.php b/version.php
index cc9cdea..7610479 100644
--- a/version.php
+++ b/version.php
@@ -22,7 +22,7 @@
 defined('MOODLE_INTERNAL') || die();
 
 $plugin->component = 'local_treestudyplan';  // Recommended since 2.0.2 (MDL-26035). Required since 3.0 (MDL-48494).
-$plugin->version = 2023112301;  // YYYYMMDDHH (year, month, day, iteration).
+$plugin->version = 2023112400;  // YYYYMMDDHH (year, month, day, iteration).
 $plugin->requires = 2021051700; // YYYYMMDDHH (This is the release version for Moodle 3.11).
 
 $plugin->release = "1.1.0-b";