diff --git a/app/Config/Schema/schema.xml b/app/Config/Schema/schema.xml
index d1c95301b..274e9af50 100644
--- a/app/Config/Schema/schema.xml
+++ b/app/Config/Schema/schema.xml
@@ -3142,6 +3142,7 @@
     <field name="group_validity_sync_window" type="I" />
     <field name="garbage_collection_interval" type="I" />
     <field name="enable_normalization" type="L" />
+    <field name="enable_ident_isearch" type="L" />
     <field name="enable_empty_cou" type="L" />
     <field name="invitation_validity" type="I" />
     <field name="permitted_fields_name" type="C" size="160" />
diff --git a/app/Controller/StandardController.php b/app/Controller/StandardController.php
index bfa173950..751fa9a81 100644
--- a/app/Controller/StandardController.php
+++ b/app/Controller/StandardController.php
@@ -839,7 +839,16 @@ public function index() {
       if(!empty($this->request->query['search_identifier'])) {
         // XXX temporary implementation -- need more general approach (CO-1053)
         $args = array();
-        $args['conditions']['Identifier.identifier'] = $this->request->query['search_identifier'];
+        // search.identifier is supported by CoDepartment, OrgIdentity, CoGroup, CoPerson API. All these requests
+        // require the coId as a query parameter
+        $CoSetting = ClassRegistry::init('CoSetting');
+        if(!empty($this->request->query['coid'])
+           && $CoSetting->identifierISearchEnabled($this->request->query['coid'])
+        ) {
+          $args['conditions']['LOWER(Identifier.identifier) LIKE'] = '%' . $this->request->query['search_identifier'] . '%';
+        } else {
+          $args['conditions']['Identifier.identifier'] = $this->request->query['search_identifier'];
+        }
 
         $orgPooled = $this->CmpEnrollmentConfiguration->orgIdentitiesPooled();
         if(!empty($this->params['url']['coid']) && !$orgPooled) {
diff --git a/app/Lib/lang.php b/app/Lib/lang.php
index cb590c2c7..d8df81adb 100644
--- a/app/Lib/lang.php
+++ b/app/Lib/lang.php
@@ -1660,6 +1660,7 @@
   'fd.id.seq' =>      'ID',
   'fd.id.val' =>      'ID: %1$s',
   // The next set must be named fd.model.validation-field
+  'fd.identifier.caseinsensitive.search.enable' => 'Enable Case Insensitive Identifier Searching',
   'fd.identifier.description' => 'Description',
   'fd.identifier.identifier' => 'Identifier',
   'fd.identifier.login' => 'Login',
diff --git a/app/Model/CoSetting.php b/app/Model/CoSetting.php
index 7f8a9fba3..254618c0d 100644
--- a/app/Model/CoSetting.php
+++ b/app/Model/CoSetting.php
@@ -84,6 +84,11 @@ class CoSetting extends AppModel {
       'required' => false,
       'allowEmpty' => true
     ),
+    'enable_ident_isearch' => array(
+      'rule' => 'boolean',
+      'required' => false,
+      'allowEmpty' => true
+    ),
     'enable_nsf_demo' => array(
       'rule' => 'boolean',
       'required' => false,
@@ -202,6 +207,7 @@ class CoSetting extends AppModel {
     'group_create_admin_only'    => false,
     'enable_normalization'       => true,
     'enable_nsf_demo'            => false,
+    'enable_ident_isearch'       => false,
     'group_validity_sync_window' => DEF_GROUP_SYNC_WINDOW,
     'invitation_validity'        => DEF_INV_VALIDITY,
     'garbage_collection_interval'  => DEF_GARBAGE_COLLECT_INTERVAL,
@@ -495,6 +501,18 @@ public function getTAndCLoginMode($coId) {
     return $this->lookupValue($coId, 't_and_c_login_mode');
   }
 
+  /**
+   * Determine if Identifier Case Insensitise search is enabled for the specified CO.
+   *
+   * @since  COmanage Registry 4.3.3
+   * @param  integer $coId CO ID
+   * @return boolean True if enabled, false otherwise
+   */
+
+  public function identifierISearchEnabled($coId) {
+    return (boolean)$this->lookupValue($coId, 'enable_ident_isearch');
+  }
+
   /**
    * Obtain a single CO setting.
    *
diff --git a/app/Model/Identifier.php b/app/Model/Identifier.php
index 68c576b3e..924934bfa 100644
--- a/app/Model/Identifier.php
+++ b/app/Model/Identifier.php
@@ -461,12 +461,17 @@ public function findCoForRecord($id) {
    * @param  integer $coId  CO ID to constrain search to
    * @param  string  $q     String to search for
    * @param  integer $limit Search limit
-   * @return Array Array of search results, as from find('all)
+   * @return Array Array of search results, as from find('all')
    */
   
   public function search($coId, $q, $limit) {
     $args = array();
-    $args['conditions']['LOWER(Identifier.identifier) LIKE'] = '%' . strtolower($q) . '%';
+    $CoSetting = ClassRegistry::init('CoSetting');
+    if($CoSetting->identifierISearchEnabled($coId)) {
+      $args['conditions']['LOWER(Identifier.identifier) LIKE'] = '%' . $q . '%';
+    } else {
+      $args['conditions']['Identifier.identifier'] = $q;
+    }
     $args['conditions']['OR'] = array(
       'CoPerson.co_id' => $coId,
       'CoGroup.co_id' => $coId