information:filtering, information:highlighting, linguistic:translation, stylistic:tone, structural:scholar_edition
Advanced techniques

Every call (including "pass", also sometimes called "no bid") serves two purposes. It confirms or passes some information to a partner, and, by implication, denies any other kind of hand which would have tended to support an alternative call. For example, a bid of 2NT immediately after partner's 1NT not only shows a balanced hand of a certain point range, but also almost always denies possession of a five-card major suit (otherwise the player would have bid it) or even a four card major suit (in that case, the player should use the Stayman convention).

Likewise, in some partnerships the bid of 2 ♥ in the sequence 1NT–2 ♣ –2 ♦ –2 ♥ between partners (opponents passing throughout) explicitly shows five hearts but also confirms four cards in spades: the bidder must hold at least five hearts to make it worth looking for a heart fit after 2 ♦ denied a four card major, and with at least five hearts, a Stayman bid must have been justified by having exactly four spades, the other major (since Stayman (as used by this partnership) is not useful with anything except a four card major suit). Thus an astute partner can read much more than the surface meaning into the bidding. Alternatively, many partnerships play this same bidding sequence as "Crawling Stayman" by which the responder shows a weak hand (less than eight high card points) with shortness in diamonds but at least four hearts and four spades; the opening bidder may correct to spades if that appears to be the better contract.

The situations detailed here are extremely simple examples; many instances of advanced bidding involve specific agreements related to very specific situations and subtle inferences regarding entire sequences of calls.