diff --git a/pbs-api-types/src/lib.rs b/pbs-api-types/src/lib.rs
index 72cddf38..a3ad185b 100644
--- a/pbs-api-types/src/lib.rs
+++ b/pbs-api-types/src/lib.rs
@@ -381,8 +381,13 @@ pub enum RealmType {
     OpenId,
     /// An LDAP realm
     Ldap,
+    /// An Active Directory (AD) realm
+    Ad,
 }
 
+serde_plain::derive_display_from_serialize!(RealmType);
+serde_plain::derive_fromstr_from_deserialize!(RealmType);
+
 #[api(
     properties: {
         realm: {