Western Cue Bid

Asks partner to bid Notrump if he has a stopper in the opponent's suit by making a non-jump bid of the suit on the 3 level before a major suit fit has been agreed upon.

Ideally, you should have a half-stopper (Qxx or Jxxx) in the suit yourself, though if you think your side can take 9 tricks off the top, you could make the cue bid with as little as xx in the suit.

Example: Axx-KJx-Qxx-Kxxx.

1 - 1 - 1- 2
3

Responder bids 3N to show a heart stopper.

Responder can bid 3N with as little as Kx in the suit since he can win the opening lead in the suit with his King, then your remaining Qx stops your RHO's AJ...