diff --git a/modules/nickserv/nickserv.rs b/modules/nickserv/nickserv.rs
index fb2af92..f9359c6 100644
--- a/modules/nickserv/nickserv.rs
+++ b/modules/nickserv/nickserv.rs
@@ -39,12 +39,18 @@ impl Service for NickServ {
                     nick: from.nick.to_string(),
                 });
             }
-            Some("IDENTIFY") => {
-                let Some(password) = args.get(1) else {
-                    ctx.notice(me, from.uid, "Syntax: IDENTIFY <password>");
-                    return;
+            Some("IDENTIFY") | Some("ID") => {
+                // IDENTIFY [account] <password> — the account defaults to the
+                // current nick, so both the bare-password and account+password forms work.
+                let (account_name, password) = match (args.get(1), args.get(2)) {
+                    (Some(account), Some(password)) => (*account, *password),
+                    (Some(password), None) => (from.nick, *password),
+                    _ => {
+                        ctx.notice(me, from.uid, "Syntax: IDENTIFY [account] <password>");
+                        return;
+                    }
                 };
-                match db.authenticate(from.nick, password) {
+                match db.authenticate(account_name, password) {
                     Some(account) => {
                         // Already identified to this account: don't re-fire the login.
                         if from.account == Some(account) {
@@ -75,7 +81,7 @@ impl Service for NickServ {
             Some("HELP") => ctx.notice(
                 me,
                 from.uid,
-                "NickServ looks after your nickname. Commands: \x02REGISTER\x02 <password> [email], \x02IDENTIFY\x02 <password>, \x02LOGOUT\x02, \x02CERT\x02 ADD|DEL|LIST <password> [fingerprint].",
+                "NickServ looks after your nickname. Commands: \x02REGISTER\x02 <password> [email], \x02IDENTIFY\x02 [account] <password>, \x02LOGOUT\x02, \x02CERT\x02 ADD|DEL|LIST <password> [fingerprint].",
             ),
             Some(other) => ctx.notice(me, from.uid, format!("I don't know the command \x02{other}\x02. Try \x02HELP\x02.")),
             None => {}
diff --git a/src/engine/mod.rs b/src/engine/mod.rs
index 2c77531..f8980bb 100644
--- a/src/engine/mod.rs
+++ b/src/engine/mod.rs
@@ -978,6 +978,25 @@ mod tests {
         assert!(out.iter().any(|a| matches!(a, NetAction::Metadata { key, value, .. } if key == "accountname" && value == "realnick")), "must log into the current nick's account: {out:?}");
     }
 
+    // IDENTIFY accepts the two-arg account+password form: log into a named
+    // account even when the current nick differs; a wrong password is refused.
+    #[test]
+    fn identify_two_arg_account_form() {
+        let mut e = engine_with("twoarg", "realacct", "sesame");
+        e.handle(NetEvent::UserConnect { uid: "000AAAAAB".into(), nick: "someguest".into(), host: "host.example".into() });
+        let out = e.handle(NetEvent::Privmsg {
+            from: "000AAAAAB".into(), to: "42SAAAAAA".into(), text: "IDENTIFY realacct sesame".into(),
+        });
+        assert!(out.iter().any(|a| matches!(a, NetAction::Metadata { key, value, .. } if key == "accountname" && value == "realacct")), "two-arg identify logs into the named account: {out:?}");
+
+        e.handle(NetEvent::UserConnect { uid: "000AAAAAC".into(), nick: "other".into(), host: "host.example".into() });
+        let bad = e.handle(NetEvent::Privmsg {
+            from: "000AAAAAC".into(), to: "42SAAAAAA".into(), text: "IDENTIFY realacct wrongpw".into(),
+        });
+        assert!(bad.iter().any(|a| matches!(a, NetAction::Notice { text, .. } if text.contains("Invalid password"))), "{bad:?}");
+        assert!(!bad.iter().any(|a| matches!(a, NetAction::Metadata { .. })), "wrong password must not log in: {bad:?}");
+    }
+
     // ChanServ: registration needs identification, INFO shows the founder, and
     // only the founder can drop.
     #[test]