Cue Bidding:

Bid of the opponents' suit

After the opponents have bid a suit, a cue bid of that suit is normally intended as a forcing bid. It shows interest in contesting the contract and asks partner to describe his hand.

Immediate cue bid

Various meanings are assigned to the immediate cue bid. The most common treatment is now the Michaels cue bid or Ghestem which may be a weakish or moderate hand with at least 5-5 in two unbid suits.

Cue bidding in the later rounds

Generally, after the opponents have bid a suit, a cue bid of that suit shows strength, and forces the bidding to continue for at least one round. The following are common situations:

• After partner's takeout double or overcall, the cue bid shows a hand with at least the strength of an opening bid:

West	North	East	South
1♥	Dbl	Pass	2♥

West	North	East	South
1♥	1♠	Pass	2♥

• A takeout double followed by a cue bid shows a very strong hand:

West	North	East	South
1♥	Dbl	Pass	1♠
Pass	2♥

• Immediately after RHO's overcall, it shows a strong hand, probably fitting partner's suit, and is usually regarded as game-forcing:

West	North	East	South
	1♥	1♠	2♠

• After RHO's overcall, in a later round but below 3NT, it often asks for a stopper in the opponents' suit, inviting partner to bid notrump and thus place the contract advantageously. This situation calls for prior partnership discussion.

Slam seeking

Once a trump suit has been agreed and the bidding cannot die below the game level (e.g. 1♥–3♥, or ... 2♥–3♥, or 1♥–1♠; 3♠), any subsequent bid of a suit other than the trump suit is a cue bid showing first round control of that suit, i.e. the ace or a void.

Passing a suit that could be bid tends to deny holding first-round control in that suit. Bids of suits already bid show second-round control. Returning to the trump suit shows a lack of interest in slam or not having anything else to bid. For example:

South	West	North	East
1♦	pass	1♥	pass
3♥	pass	4♣	pass
4♦	pass	4♥	pass
4♠	pass	4NT	pass

South has shown 16-18 total points, while North's hand is largely unknown. North's bid of 4♣ is a cue-bid showing first-round control of clubs and an interest in slam. After South's bid of 4♦ North bids 4♥, an apparent signoff. It may well be that North wants to bid a slam, but has two fast losers in the spade suit. After South bids 4♠ showing control of the spade suit, North uses the Blackwood convention to proceed further.

The main disadvantage of both Blackwood and Gerber is that they give little information about voids, which can be as powerful as aces under certain circumstances. Cue bidding is designed to pass information on "first round control" i.e. an ace or a void.

Basic cue bidding

In "basic cue bidding", after the trump suit has been agreed (implicitly or explicitly), the first bid of a side suit by either partner shows a control. The most common approach is that first-round controls are bid first, and second-round controls are bid in later rounds of bidding. Accurate cue bidding therefore requires perfect partnership understanding.