diff --git a/config.php b/config.php
index 5608497..a26a4cd 100644
--- a/config.php
+++ b/config.php
@@ -4,14 +4,16 @@
 define('API_TOKEN', getenv('API_TOKEN') ?: '');
 define('DEMO', false);
 define('JWT_ENABLED', getenv('JWT_ENABLED')?: false);
+define('DESIRED_ATTRIBUTE_TO_DISCLOSE', getenv('DESIRED_ATTRIBUTE_TO_DISCLOSE') ?: '');
+
 
 if (DEMO) {
-    define('ISSUER', 'irma-demo');
+    define('SCHEME', 'irma-demo');
     define('BASE_URL', 'http://localhost:8080'); 
     define('IRMATUBE_NEXT_SESSION_URL', BASE_URL . '/get_session_request.php');
     define('IRMATUBE_CREDENTIAL', 'irma-demo.IRMATube.member');
 } else {
-    define('ISSUER',getenv('ISSUER') ?: 'pbdf');
+    define('SCHEME',getenv('SCHEME') ?: 'pbdf');
     define('BASE_URL', getenv('BASE_URL') ?: 'https://privacybydesign.foundation');
     define('IRMATUBE_NEXT_SESSION_URL',getenv('IRMATUBE_NEXT_SESSION_URL') ?: BASE_URL . '/get_session_request.php');
     define('IRMATUBE_CREDENTIAL',  getenv('IRMATUBE_CREDENTIAL') ?: 'pbdf.pbdf.irmatube');
diff --git a/start_session.php b/start_session.php
index ac6e190..83c66e9 100644
--- a/start_session.php
+++ b/start_session.php
@@ -141,10 +141,11 @@
             'disclose' => [
                 array_merge(
                     [
-                        [ISSUER .'.pbdf.linkedin.familyname'],
-                        [ISSUER .'.gemeente.personalData.fullname'],
+                        [SCHEME .'.pbdf.linkedin.familyname'],
+                        [SCHEME .'.gemeente.personalData.fullname'],
+                        DESIRED_ATTRIBUTE_TO_DISCLOSE ? [SCHEME . DESIRED_ATTRIBUTE_TO_DISCLOSE] : [],
                     ],
-                    ISSUER === 'pbdf' ? [
+                    SCHEME === 'pbdf' ? [
                         ['pbdf.pilot-amsterdam.idcard.surname'],
                         ['pbdf.pilot-amsterdam.passport.surname'],
                     ] : [] // These credential types have no equivalent in irma-demo