diff --git a/src/CivicrmMemberRoles.php b/src/CivicrmMemberRoles.php
index c6786c7..fb58070 100644
--- a/src/CivicrmMemberRoles.php
+++ b/src/CivicrmMemberRoles.php
@@ -222,2 +222,5 @@ class CivicrmMemberRoles {
       $params = ['uf_id' => $account->id()];
+      if ($domain_id = constant('CIVICRM_DOMAIN_ID')) {
+          $params['domain_id'] = $domain_id;
+      }
       $this->civicrm->initialize();