HAMILTON CONVENTION
This conventional defense method was devised by Mr. Fred Hamilton of California. After the opponents open No Trump, the Hamilton convention is a defensive bid either in the direct seat or in the balancing seat. It resembles Cappelletti and Bergen in some ways, but has different meanings to the individual bids. The overcalls and responses are listed below. Source: OEB179.
Overcaller - Intervenor Responder - Advancer 2 is a forcing bid showing a One-Suiter. Partner must bid 2
.
The most important thing to remember is the fact that the bidding so far says nothing about these 2 suits. After the forced 2 response from his partner, the overcaller names his suit. If it is Diamonds, he may pass.
Other Overcalls show Two-Suited Hands: Meanings 2 :
Spades and Hearts 2 :
Hearts and unspecified Minor Suit.
If responder wants to find out which Minor, responder bids 2 No Trump.2 :
Spades and unspecified Minor Suit
If responder wants to find out which Minor, responder bids 2 No Trump.2 No Trump: Both Minor Suits. Double: Primarily for penalty, partner can pass.
Each convention used in entering the auction, after one opponent has described his hand exactly, should be studied and applied correctly. In most cases, the opponents will not reach game. Game is possible, however, since the location of the strength by the opponents is a known factor. Reaching the correct contract is the target of the overcaller and his partner, and these different conventions can be useful tools.
Double: Penalty Double 2 :
Promises either a single-suit in Diamonds or Hearts and an unspecified Minor suit or Spades and an unspecified Minor suit. 2 :
Promises both Major suits. 2 :
Promises a single-suit in Hearts. 2 :
Promises a single-suit in Spades.
In the case that the overcaller is already a passed hand, then the overcall changes somewhat as in the following manner:
Double: Promises a single-suit in Clubs / Diamonds / Hearts / Spades and a shorter unspecified Minor suit. 2 :
Promises both Minor suits. 2 :
Promises both Major suits. 2 :
Promises a single-suit in Hearts. 2 :
Promises a single-suit in Spades.
Generally after a double, if the rebid of the overcaller is Clubs, then the Club suit is the longer, stronger suit and the Diamond suit is the second, shorter suit. If, on the other hand, the rebid of the overcaller is Diamonds, then the Diamond suit is the longer, stronger suit and the Club suit is the second, shorter suit. If a relay bid of 2 Clubs (totally artificial) is used by the advancer, then a raise of one level in Clubs by the overcaller promises Clubs and additional values and a game contract may be considered. Knowing that Diamonds is the second, shorter suit, the advancer may also correct to Diamonds. If, however, the overcaller passes, then this pass promises that the single suit is Clubs and indicates weakness. If a relay bid of 2 Clubs is used by the advancer and the rebid by the overcaller is two Diamonds, which also promises Clubs as the second, shorter suit, then the advancer may correct to Clubs as a preference.
In order to discover the single-suit the partnership may employ any method. In order to show additional values, the partnership may also decide to employ jump bids. The cuebid of 2 No Trump is left to the partnership as to whether this bid should be assigned any significance. All responses are per partnership agreement.