diff --git a/mod/assign/amd/build/participant_selector.min.js b/mod/assign/amd/build/participant_selector.min.js
index f7f393b1767..23a7ce58b27 100644
--- a/mod/assign/amd/build/participant_selector.min.js
+++ b/mod/assign/amd/build/participant_selector.min.js
@@ -1 +1 @@
-define(["core/ajax","jquery","core/templates"],function(a,b,c){return{processResults:function(a,b){var c=[],d=0;for(d=0;d<b.length;d++)c[d]={value:b[d].id,label:b[d].label};return c},transport:function(d,e,f,g){var h=b(d).attr("data-assignmentid"),i=b('[data-region="configure-filters"] input[type="checkbox"]'),j=[];i.each(function(a,c){j[b(c).attr("name")]=b(c).prop("checked")});var k=a.call([{methodname:"mod_assign_list_participants",args:{assignid:h,groupid:0,filter:e,limit:30}}]);k[0].then(function(a){var d=[],e=b("[data-showuseridentity]").data("showuseridentity").split(",");b.each(a,function(a,f){var g=f,h=[],i=!0;j.filter_submitted&&!f.submitted&&(i=!1),j.filter_notsubmitted&&f.submitted&&(i=!1),j.filter_requiregrading&&!f.requiregrading&&(i=!1),i&&(b.each(e,function(a,b){"undefined"!=typeof f[b]&&""!==f[b]&&(g.hasidentity=!0,h.push(f[b]))}),g.identity=h.join(", "),d.push(c.render("mod_assign/list_participant_user_summary",g)))}),b.when.apply(b.when,d).then(function(){var c=arguments,d=0;b.each(a,function(a,b){b.label=c[d],d++}),f(a)})},g)}}});
\ No newline at end of file
+define(["core/ajax","jquery","core/templates"],function(a,b,c){return{processResults:function(a,b){var c=[],d=0;for(d=0;d<b.length;d++)c[d]={value:b[d].id,label:b[d].label};return c},transport:function(d,e,f,g){var h=b(d).attr("data-assignmentid"),i=b('[data-region="configure-filters"] input[type="checkbox"]'),j=[];i.each(function(a,c){j[b(c).attr("name")]=b(c).prop("checked")});var k=a.call([{methodname:"mod_assign_list_participants",args:{assignid:h,groupid:0,filter:e,limit:30,includeenrolments:!1}}]);k[0].then(function(a){var d=[],e=b("[data-showuseridentity]").data("showuseridentity").split(",");b.each(a,function(a,f){var g=f,h=[],i=!0;j.filter_submitted&&!f.submitted&&(i=!1),j.filter_notsubmitted&&f.submitted&&(i=!1),j.filter_requiregrading&&!f.requiregrading&&(i=!1),i&&(b.each(e,function(a,b){"undefined"!=typeof f[b]&&""!==f[b]&&(g.hasidentity=!0,h.push(f[b]))}),g.identity=h.join(", "),d.push(c.render("mod_assign/list_participant_user_summary",g)))}),b.when.apply(b.when,d).then(function(){var c=arguments,d=0;b.each(a,function(a,b){b.label=c[d],d++}),f(a)})},g)}}});
\ No newline at end of file
diff --git a/mod/assign/amd/src/participant_selector.js b/mod/assign/amd/src/participant_selector.js
index 71312a68acc..f92f4fb82db 100644
--- a/mod/assign/amd/src/participant_selector.js
+++ b/mod/assign/amd/src/participant_selector.js
@@ -62,7 +62,8 @@ define(['core/ajax', 'jquery', 'core/templates'], function(ajax, $, templates) {
             });
 
             var promise = ajax.call([{
-                methodname: 'mod_assign_list_participants', args: {assignid: assignmentid, groupid: 0, filter: query, limit: 30}
+                methodname: 'mod_assign_list_participants',
+                args: {assignid: assignmentid, groupid: 0, filter: query, limit: 30, includeenrolments: false}
             }]);
 
             promise[0].then(function(results) {
diff --git a/mod/assign/externallib.php b/mod/assign/externallib.php
index f87d91d6b0a..bb9598380a1 100644
--- a/mod/assign/externallib.php
+++ b/mod/assign/externallib.php
@@ -2510,6 +2510,8 @@ class mod_assign_external extends external_api {
                 'skip' => new external_value(PARAM_INT, 'number of records to skip', VALUE_DEFAULT, 0),
                 'limit' => new external_value(PARAM_INT, 'maximum number of records to return', VALUE_DEFAULT, 0),
                 'onlyids' => new external_value(PARAM_BOOL, 'Do not return all user fields', VALUE_DEFAULT, false),
+                'includeenrolments' => new external_value(PARAM_BOOL, 'Do return courses where the user is enrolled',
+                                                          VALUE_DEFAULT, true)
             )
         );
     }
@@ -2523,11 +2525,12 @@ class mod_assign_external extends external_api {
      * @param int $skip Number of records to skip
      * @param int $limit Maximum number of records to return
      * @param bool $onlyids Only return user ids.
+     * @param bool $includeenrolments Return courses where the user is enrolled.
      * @return array of warnings and status result
      * @since Moodle 3.1
      * @throws moodle_exception
      */
-    public static function list_participants($assignid, $groupid, $filter, $skip, $limit, $onlyids) {
+    public static function list_participants($assignid, $groupid, $filter, $skip, $limit, $onlyids, $includeenrolments) {
         global $DB, $CFG;
         require_once($CFG->dirroot . "/mod/assign/locallib.php");
         require_once($CFG->dirroot . "/user/lib.php");
@@ -2539,7 +2542,8 @@ class mod_assign_external extends external_api {
                                                 'filter' => $filter,
                                                 'skip' => $skip,
                                                 'limit' => $limit,
-                                                'onlyids' => $onlyids
+                                                'onlyids' => $onlyids,
+                                                'includeenrolments' => $includeenrolments
                                             ));
         $warnings = array();
 
@@ -2551,6 +2555,17 @@ class mod_assign_external extends external_api {
 
         $participants = $assign->list_participants_with_filter_status_and_group($params['groupid']);
 
+        $userfields = user_get_default_fields();
+        if (!$params['includeenrolments']) {
+            // Remove enrolled courses from users fields to be returned.
+            $key = array_search('enrolledcourses', $userfields);
+            if ($key !== false) {
+                unset($userfields[$key]);
+            } else {
+                throw new moodle_exception('invaliduserfield', 'error', '', 'enrolledcourses');
+            }
+        }
+
         $result = array();
         $index = 0;
         foreach ($participants as $record) {
@@ -2577,7 +2592,7 @@ class mod_assign_external extends external_api {
                 }
                 // Now we do the expensive lookup of user details because we completed the filtering.
                 if (!$assign->is_blind_marking() && !$params['onlyids']) {
-                    $userdetails = user_get_user_details($record, $course);
+                    $userdetails = user_get_user_details($record, $course, $userfields);
                 } else {
                     $userdetails = array('id' => $record->id);
                 }
@@ -2620,7 +2635,6 @@ class mod_assign_external extends external_api {
         $userdesc->keys['profileimageurlsmall']->required = VALUE_OPTIONAL;
         $userdesc->keys['profileimageurl']->required = VALUE_OPTIONAL;
         $userdesc->keys['email']->desc = 'Email address';
-        $userdesc->keys['email']->desc = 'Email address';
         $userdesc->keys['idnumber']->desc = 'The idnumber of the user';
 
         // Define other keys.
diff --git a/mod/assign/tests/externallib_test.php b/mod/assign/tests/externallib_test.php
index d4c17e040fb..b97b84bb78b 100644
--- a/mod/assign/tests/externallib_test.php
+++ b/mod/assign/tests/externallib_test.php
@@ -2386,7 +2386,7 @@ class mod_assign_external_testcase extends externallib_advanced_testcase {
         $DB->update_record('user', $student);
 
         $this->setUser($teacher);
-        $participants = mod_assign_external::list_participants($assignment->id, 0, '', 0, 0, false);
+        $participants = mod_assign_external::list_participants($assignment->id, 0, '', 0, 0, false, true);
         $this->assertCount(1, $participants);
 
         // Asser that we have a valid response data.
@@ -2401,6 +2401,12 @@ class mod_assign_external_testcase extends externallib_advanced_testcase {
         $this->assertEquals($student->phone2, $participant['phone2']);
         $this->assertEquals($student->department, $participant['department']);
         $this->assertEquals($student->institution, $participant['institution']);
+        $this->assertArrayHasKey('enrolledcourses', $participant);
+
+        $participants = mod_assign_external::list_participants($assignment->id, 0, '', 0, 0, false, false);
+        // Check that the list of courses the participant is enrolled is not returned.
+        $participant = $participants[0];
+        $this->assertArrayNotHasKey('enrolledcourses', $participant);
     }
 
     /**
diff --git a/user/tests/userlib_test.php b/user/tests/userlib_test.php
index 72aebbba964..a293dacd14e 100644
--- a/user/tests/userlib_test.php
+++ b/user/tests/userlib_test.php
@@ -575,4 +575,52 @@ class core_userliblib_testcase extends advanced_testcase {
 
         $CFG->coursecontact = null;
     }
+
+    /**
+     * Test user_get_user_details
+     */
+    public function test_user_get_user_details() {
+        global $DB;
+
+        $this->resetAfterTest();
+
+        // Create user and modify user profile.
+        $teacher = $this->getDataGenerator()->create_user();
+        $student = $this->getDataGenerator()->create_user();
+        $studentfullname = fullname($student);
+
+        $course1 = $this->getDataGenerator()->create_course();
+        $coursecontext = context_course::instance($course1->id);
+        $teacherrole = $DB->get_record('role', array('shortname' => 'teacher'));
+        $studentrole = $DB->get_record('role', array('shortname' => 'student'));
+        $this->getDataGenerator()->enrol_user($teacher->id, $course1->id);
+        $this->getDataGenerator()->enrol_user($student->id, $course1->id);
+        role_assign($teacherrole->id, $teacher->id, $coursecontext->id);
+        role_assign($studentrole->id, $student->id, $coursecontext->id);
+
+        accesslib_clear_all_caches_for_unit_testing();
+
+        // Get student details as a user with super system capabilities.
+        $result = user_get_user_details($student, $course1);
+        $this->assertEquals($student->id, $result['id']);
+        $this->assertEquals($studentfullname, $result['fullname']);
+        $this->assertEquals($course1->id, $result['enrolledcourses'][0]['id']);
+
+        $this->setUser($teacher);
+        // Get student details as a user who can only see this user in a course.
+        $result = user_get_user_details($student, $course1);
+        $this->assertEquals($student->id, $result['id']);
+        $this->assertEquals($studentfullname, $result['fullname']);
+        $this->assertEquals($course1->id, $result['enrolledcourses'][0]['id']);
+
+        // Get student details with required fields.
+        $result = user_get_user_details($student, $course1, array('id', 'fullname'));
+        $this->assertCount(2, $result);
+        $this->assertEquals($student->id, $result['id']);
+        $this->assertEquals($studentfullname, $result['fullname']);
+
+        // Get exception for invalid required fields.
+        $this->expectException('moodle_exception');
+        $result = user_get_user_details($student, $course1, array('wrongrequiredfield'));
+    }
 }