diff --git a/data/cdata/scripts/mp/team_balance.gsc b/data/cdata/scripts/mp/team_balance.gsc
new file mode 100644
index 00000000..759aceb2
--- /dev/null
+++ b/data/cdata/scripts/mp/team_balance.gsc
@@ -0,0 +1,27 @@
+init()
+{
+    // define the auto balance string in the game array (referenced in gsc dump, but not defined past IW6?)
+    precachestring(&"MP_AUTOBALANCE_NOW");
+    game["strings"]["autobalance"] = &"MP_AUTOBALANCE_NOW";
+
+    // define onteamselection callback function used in balanceteams()
+    level.onteamselection = ::set_team;
+}
+
+set_team(team)
+{
+    if (team != self.pers["team"])
+    {
+        self.switching_teams = true;
+        self.joining_team = team;
+        self.leaving_team = self.pers["team"];
+    }
+
+    if (self.sessionstate == "playing")
+    {
+        self suicide();
+    }
+
+    maps\mp\gametypes\_menus::addtoteam(team);
+    maps\mp\gametypes\_menus::endrespawnnotify();
+}