In the partnership card game contract bridge, the San Francisco convention is a slam bidding convention, or a special usage by partnership agreement in order to help choose among the five, six, and seven levels for the final contract. One partner bids 4NT to ask, and the other replies, in code, to show aces and kings in one bid. Thus it is an alternative to the Blackwood convention family.
The San Francisco reply is usually sufficient for partner to infer the precise numbers of aces and kings in the replying hand, hence in the two partnership hands. So it is useful where partner can choose the contract level by knowing the numbers of aces and kings that are "missing" in the two opposing hands.
The San Francisco scale is three points for an ace, one for a king. The asking bid is 4NT with these replies:
- 5♣ : 0 to 2 points, i.e. 0 to 2 kings only
- 5♦ : 3 points
- 5♥ : 4 points
- 5♠ : 5 points
- 5NT : 6 points, i.e. two aces or one ace and three kings
- etc.
Except for 5♣=0–2, 5♠=5, and 6♦=8, the replies are equivocal with reference to the entire 52-card pack, but the other replies may be unequivocal given reference to another hand, typically partner's hand. For example, if partner holds two kings then 5NT must be two aces.
The San Francisco replies take so much space that a weak or medium-strength hand may need to investigate slam by other methods.
As slam bidding conventions at or near the 4NT level, San Francisco and Norman four notrump have been superseded by the Blackwood convention and its variants, which show at once only the number of aces or keycards, and show kings subsequently if at all.
Famous quotes containing the words san francisco, san, francisco and/or convention:
“We had won. Pimps got out of their polished cars and walked the streets of San Francisco only a little uneasy at the unusual exercise. Gamblers, ignoring their sensitive fingers, shook hands with shoeshine boys.... Beauticians spoke to the shipyard workers, who in turn spoke to the easy ladies.... I thought if war did not include killing, Id like to see one every year. Something like a festival.”
—Maya Angelou (b. 1928)
“the San Marco Library,
Whence turbulent Italy should draw
Delight in Art whose end is peace,
In logic and in natural law
By sucking at the dugs of Greece.”
—William Butler Yeats (18651939)
“Today, San Francisco has experienced a double tragedy of incredible proportions. As acting mayor, I order an immediate state of mourning in our city. The city and county of San Francisco must and will pull itself together at this time. We will carry on as best as we possibly can.... I think we all have to share the same sense of shame and the same sense of outrage.”
—Dianne Feinstein (b. 1933)
“Every one knows about the young man who falls in love with the chorus-girl because she can kick his hat off, and his sisters friends cant or wont. But the youth who marries her, expecting that all her departures from convention will be as agile or as delightful to him as that, is still the classic example of folly.”
—Katharine Fullerton Gerould (18791944)