diff --git a/classes/domain/autogroup_set.php b/classes/domain/autogroup_set.php
index 8f1cafe..87d09ed 100644
--- a/classes/domain/autogroup_set.php
+++ b/classes/domain/autogroup_set.php
@@ -100,6 +100,7 @@ public function delete(\moodle_database $db, $cleanupgroups = true)
         //this has to be done first to prevent event handler getting in the way
         $db->delete_records('local_autogroup_set', array('id'=>$this->id));
         $db->delete_records('local_autogroup_roles', array('setid'=>$this->id));
+        $db->delete_records('local_autogroup_manual', array('groupid'=>$this->id));
 
         if($cleanupgroups){
             foreach($this->groups as $k => $group){
diff --git a/classes/domain/group.php b/classes/domain/group.php
index c487398..6e49acb 100644
--- a/classes/domain/group.php
+++ b/classes/domain/group.php
@@ -90,6 +90,16 @@ public function ensure_user_is_member($userid){
      * @param int $userid
      */
     public function ensure_user_is_not_member($userid){
+
+        // Do not allow autogroup to remove this User if they were manually assigned to group.
+        $pluginconfig = get_config('local_autogroup');
+        if($pluginconfig->preservemanual) {
+            global $DB;
+            if($DB->record_exists('local_autogroup_manual', array('userid' => $userid, 'groupid' => $this->id))) {
+                return;
+            }
+        }
+
         foreach($this->members as $member){
             if ($member == $userid) {
                 \groups_remove_member($this->as_object(), $userid);
diff --git a/classes/event_handler.php b/classes/event_handler.php
index 8c8feb5..2cabdc4 100644
--- a/classes/event_handler.php
+++ b/classes/event_handler.php
@@ -76,13 +76,22 @@ public static function group_member_added(event\group_member_added $event) {
             return false;
         }
 
+        global $DB;
         $pluginconfig = get_config('local_autogroup');
+
+        // Add to manually assigned list (local_autogroup_manual).
+        $userid = (int) $event->relateduserid;
+        $groupid = (int) $event->objectid;
+
+        if(!$DB->record_exists('local_autogroup_manual', array('userid' => $userid, 'groupid' => $groupid))) {
+            $record = (object) array('userid' => $userid, 'groupid' => $groupid);
+            $DB->insert_record('local_autogroup_manual', $record);
+        }
+
         if(!$pluginconfig->listenforgroupmembership){
             return false;
         }
 
-        global $DB;
-
         $courseid = (int) $event->courseid;
         $userid = (int) $event->relateduserid;
 
@@ -101,10 +110,16 @@ public static function group_member_removed(event\group_member_removed $event) {
             return false;
         }
 
+        global $DB, $PAGE;
         $pluginconfig = get_config('local_autogroup');
 
+        // Remove from manually assigned list (local_autogroup_manual).
+        $userid = (int) $event->relateduserid;
+        $groupid = (int) $event->objectid;
 
-        global $DB, $PAGE;
+        if($DB->record_exists('local_autogroup_manual', array('userid' => $userid, 'groupid' => $groupid))) {
+            $DB->delete_records('local_autogroup_manual', array('userid' => $userid, 'groupid' => $groupid));
+        }
 
         $groupid = (int) $event->objectid;
         $courseid = (int) $event->courseid;
@@ -174,16 +189,21 @@ public static function group_change(event\base $event) {
             return false;
         }
 
-        $pluginconfig = get_config('local_autogroup');
-        if(!$pluginconfig->listenforgroupchanges){
-            return false;
-        }
-
         global $DB, $PAGE;
 
         $courseid = (int) $event->courseid;
         $groupid = (int) $event->objectid;
 
+        // Remove from manually assigned list (local_autogroup_manual).
+        if ($event->eventname === '\core\event\group_deleted') {
+            $DB->delete_records('local_autogroup_manual', array('groupid' => $groupid));
+        }
+
+        $pluginconfig = get_config('local_autogroup');
+        if(!$pluginconfig->listenforgroupchanges){
+            return false;
+        }
+
         if($DB->record_exists('groups', array('id'=>$groupid))) {
             $verifygroupidnumber = new usecase\verify_group_idnumber($groupid, $DB, $PAGE);
             $verifygroupidnumber();
diff --git a/db/install.xml b/db/install.xml
index ef2a572..8d045a1 100644
--- a/db/install.xml
+++ b/db/install.xml
@@ -29,5 +29,15 @@
                 <KEY NAME="roleid" TYPE="foreign" FIELDS="roleid" REFTABLE="role" REFFIELDS="id"/>
             </KEYS>
         </TABLE>
+        <TABLE NAME="local_autogroup_manual" COMMENT="Tracks manually assigned Users to autogroup groups">
+            <FIELDS>
+                <FIELD NAME="id" TYPE="int" LENGTH="10" NOTNULL="true" SEQUENCE="true"/>
+                <FIELD NAME="groupid" TYPE="int" LENGTH="10" NOTNULL="true" SEQUENCE="false" COMMENT="Group ID of this record."/>
+                <FIELD NAME="userid" TYPE="int" LENGTH="10" NOTNULL="true" SEQUENCE="false" COMMENT="User ID of this record." />
+            </FIELDS>
+            <KEYS>
+                <KEY NAME="primary" TYPE="primary" FIELDS="id"/>
+            </KEYS>
+        </TABLE>
     </TABLES>
 </XMLDB>
\ No newline at end of file
diff --git a/db/upgrade.php b/db/upgrade.php
index cdb0dee..3107169 100644
--- a/db/upgrade.php
+++ b/db/upgrade.php
@@ -19,5 +19,27 @@ function xmldb_local_autogroup_upgrade($oldversion) {
         // savepoint reached.
         upgrade_plugin_savepoint(true, 2016062201, 'local', 'autogroup');
     }
+
+    if ($oldversion < 2018102300) {
+        // Define table local_autogroup_manual to be created.
+        $table = new xmldb_table('local_autogroup_manual');
+
+        // Adding fields to table local_autogroup_manual.
+        $table->add_field('id', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, XMLDB_SEQUENCE, null);
+        $table->add_field('groupid', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, null);
+        $table->add_field('userid', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, null);
+
+        // Adding keys to table local_autogroup_manual.
+        $table->add_key('primary', XMLDB_KEY_PRIMARY, array('id'));
+
+        // Conditionally launch create table for local_autogroup_manual.
+        if (!$dbman->table_exists($table)) {
+            $dbman->create_table($table);
+        }
+
+        // Autogroup savepoint reached.
+        upgrade_plugin_savepoint(true, 2018102300, 'local', 'autogroup');
+    }
+
     return true;
-}
\ No newline at end of file
+}
diff --git a/lang/en/local_autogroup.php b/lang/en/local_autogroup.php
index fb1ca0f..9d3921f 100644
--- a/lang/en/local_autogroup.php
+++ b/lang/en/local_autogroup.php
@@ -55,6 +55,7 @@
 // Admin Settings
 $string['addtonewcourses'] = 'Add to new courses';
 $string['addtorestoredcourses'] = 'Add to restored courses';
+$string['preservemanual'] = 'Manually added Users are not removed when autogroups are updated.';
 $string['defaults'] = 'Default Settings';
 $string['defaultroles'] = 'Default Eligible Roles';
 $string['enabled'] = 'Enabled';
diff --git a/settings.php b/settings.php
index aefa138..8060832 100644
--- a/settings.php
+++ b/settings.php
@@ -75,6 +75,14 @@
             false
         )
     );
+    $settings->add(
+        new admin_setting_configcheckbox(
+            'local_autogroup/preservemanual',
+            get_string('preservemanual', 'local_autogroup'),
+            '',
+            1
+        )
+    );
 
     // default settings
     $settings->add(