Acol is the bridge bidding system that, according to The Official Encyclopedia of Bridge , [1] is "standard in British tournament play and widely used in other parts of the world". It is a natural system using four-card majors and, most commonly, a weak no trump.
Acol is named after the Acol Bridge Club in London NW6, where it originated in the early 1930s. [2] The club was founded on Acol Road, [2] named after Acol, Kent. [3] According to Terence Reese, the system's main devisers were Maurice Harrison-Gray, Jack Marx and S. J. "Skid" Simon. [4] Marx wrote in the Contract Bridge Journal of December 1952, that "...the Acol system was pieced together by Skid Simon and myself the best part of 20 years ago." [5] In another account, Marx and Simon...
progressively, infected and re-infected each other with the virus of the game. In interminable slow walks... they would wander round and round the quiet streets, endlessly discussing the refinements of the enthralling game. Out of these conversations—surely a strange gestation—was born Acol as we know it and play it to-day.
— Guy Ramsay, Aces All (1955), Museum Press Limited, London, p. 170.
The first book on the system was written by Ben Cohen and Terence Reese. [6] Skid Simon explained the principles that lay behind the system, [7] and the system was further popularised in Britain by Iain Macleod. [8] The Acol system is continually evolving but the underlying principle is to keep the bidding as natural as possible. It is common in the British Commonwealth but rarely played in North America.
Ely Culbertson and his partner Teddy Lightner had visited the Acol Bridge Club in 1934, after which members S.J. Simon and Jack Marx became interested in bridge bidding theory. Simon and Marx soon afterwards began a discussion that eventually led to the first version of the Acol system. [9]
As a bidding system, Acol has the following characteristics:
Acol is an unregulated system. There is no Acol governing body and no single publication containing the "official" Acol (unlike, for example, Standard American Yellow Card). It can be compared to a living language since it is liable to change at the whim of users. The main versions of Acol in use today are:
The following is a brief summary of the Standard Acol as from 2000 to 2005. Standard Acol has not changed significantly since that time.
Opening bids promise at least 12 high card points (HCP), or the equivalent in HCP and shape, unless preempting. Apart from NT, opening bids guarantee the ability to make a rebid over any forcing response from partner. There are six special opening bids which are quite closely defined, and one wide-ranging opening bid:
The wide-ranging 1 of a suit bid is the most common opening bid, accounting for about 75–80% of opening bids. The 1NT opening occurs on about 20% of biddable hands if "weak", or 10% if "strong".
Note 1: these last three bids may conceal 4-card support for opener's suit, whereas the three NT responses deny 4-card support for opener, and also normally deny holding a 4 card major biddable at the 1 level
Note 2: when supporting opener's suit with an 8-card fit or better, HCP ranges can be adjusted downwards slightly to allow for shortages (singletons or voids)
Note 3: with at least four-card support for opener's major and 13+ HCP, bid a new suit and then jump to 4 of opener's suit on the next round, a delayed game raise. Alternatively, by partnership agreement, the Jacoby 2NT or an alternative method may be used.
The responses below assume a weak (12–14) NT opening: players should adjust the point ranges for responses if playing a different opening range.
Rebid own suit
Note: when supporting responder's suit with an 8-card fit or better, HCP ranges can be adjusted downwards slightly to allow for shortages (singletons or voids)
The following bids assume a weak (12–14) NT opening.
The traditional rebids are:
However, the modern approach modifies the ranges for the rebids thus:
The traditional rebids are:
The modern approach is to use the 2NT rebid as forcing to game with 15–19 points, allowing major suit fits to be found at the 3 level. 3NT may be used as 15–17 with support for the minor that responder has bid (one option).
After the opener's 2NT rebid, 3♣ can be used as a (forcing) enquiry to seek definition of the 2NT rebid.
The only non-forcing bid by responder after opener's 2NT rebid is a rebid of responder's suit. This means that bidding opener's first suit is unconditionally forcing.
By the time responder has to rebid, it is often clear what the best final contract should be, especially if either player has made a limit bid. If opener has bid two suits, responder can show preference between them. With a strong hand but uncertain whether a game contract is on or which game it should be, he can use fourth suit forcing to obtain further information.
A bid of the fourth suit at the 2 level by responder is a one-round force, usually asking opener to bid no trumps with a stopper in the fourth suit. A fourth suit bid at the 3 level is similar, but forcing to game.
Suit overcalls promise at least 5 cards.
Jump overcalls promise at least 6 cards, but may be played as weak, intermediate or strong. BfA Acol uses intermediate (opening hand, 11–16 points).
1NT overcall typically promises 15–18 points and at least one stopper in opponents' suit.
Double is for takeout, showing an opening hand (12+ points) short in opponents' suit (occasionally a very strong hand, at least 16+ points, of other shapes)
Generally similar to unopposed bidding, but with these differences:
In common usage, the term Acol is understood to refer to a four-card majors system. For hybrid systems using the weak NT opening with one or both five-card majors, a different terminology is preferable.
Stayman is a bidding convention in the card game contract bridge. It is used by a partnership to find a 4-4 or 5-3 trump fit in a major suit after making a one notrump (1NT) opening bid and it has been adapted for use after a 2NT opening, a 1NT overcall, and many other natural notrump bids.
2/1 game forcing is a bidding system in modern contract bridge structured around the following responses to a one-level opening bid:
Polish Club is a bridge bidding system which was developed in Poland, where it is the most popular bidding system, and which is also used by players of other countries. It is a type of small club system.
A game try in the card game of bridge is a bid that shows interest in bidding a game and asks partner to help in making the decision.
The forcing notrump is a bidding convention in the card game of bridge.
The Jacoby transfer, or simply transfers, in the card game contract bridge, is a convention in most bridge bidding systems initiated by responder following partner's notrump opening bid that forces opener to rebid in the suit ranked just above that bid by responder. For example, a response in diamonds forces a rebid in hearts and a response in hearts forces a rebid in spades. Transfers are used to show a long suit, usually a major, and to ensure that opener declare the hand if the final contract is in the suit transferred to, preventing the opponents from seeing the cards of the stronger hand.
Zar Points (ZP) is a statistically derived method for evaluating contract bridge hands developed by Zar Petkov. The statistical research Petkov conducted in the areas of hand evaluation and bidding is useful to bridge players, regardless of their bidding or hand evaluation system. The research showed that the Milton Work point count method, even when adjusted for distribution, is not sufficiently accurate in evaluating all hands. As a result, players often make incorrect or sub-optimal bids. Zar Points are designed to take many additional factors into consideration by assigning points to each factor based on statistical weight. While most of these factors are already implicitly taken into account by experienced players, Zar Points provides a quantitative method that allows them to be incorporated into bidding.
Preempt is a bid in contract bridge whose primary objectives are (1) to thwart opponents' ability to bid to their best contract, with some safety, and (2) to fully describe one's hand to one's partner in a single bid. A preemptive bid is usually made by jumping, i.e. skipping one or more bidding levels. Since it deprives the opponents of the bidding space, it is expected that they will either find a wrong contract of their own, or fail to find any. A preemptive bid often has the aim of a save, where a partnership bids a contract knowing it cannot be made, but assumes that, the penalty will still be smaller than the value of opponents' bid and made contract.
Flannery is a bridge convention using a 2♦ opening bid to show a hand of minimal opening bid strength with exactly four spades and five hearts. It was invented by American player William (Bill) L. Flannery.
Jacoby 2NT is a bridge convention in which a bid of 2NT over partner's opening bid of one heart or one spade shows a hand with both
Bridge bidding systems that incorporate a strong 2 clubs opening bid include modern Standard American, standard Acol, 2/1 game forcing and many others.
In contract bridge, an overcall is a bid made after an opening bid has been made by an opponent; the term refers only to the first such bid. A direct overcall is such a bid made by the player seated immediately to the left of the opener, i.e. next in the bidding rotation; an overcall in the 'last seat', i.e. by the player to the right of opener, which is made after two intervening passes, is referred to as a balancing or protective overcall.
The Kaplan–Sheinwold bidding system was developed and popularized by Edgar Kaplan and Alfred Sheinwold during their partnership, which flourished during the 1950s and 1960s. K-S is one of many natural systems. The system was definitively described in their 1958 book How to Play Winning Bridge and later revised and retitled to The Kaplan-Sheinwold System of Winning Bridge in 1963.
A reverse, in the card game contract bridge, is a bidding sequence designed to show additional strength without the need to make a jump bid; specifically two suits are bid in the reverse order to that expected by the basic bidding system. Precise methods and definitions vary with country, bidding system and partnership agreements.
EHAA is a highly natural bidding system in contract bridge characterized by four-card majors, sound opening bids, undisciplined weak two-bids in all four suits and a mini notrump, usually of 10–12 high card points.
The Boring Club is a bidding system in the card game contract bridge, designed by Lucas Smid of the Netherlands. In this system all balanced ('boring') hands, that in most natural systems would be opened 1NT or would be opened in a suit at one level with the plan to rebid 1NT or 2NT, must be opened with 1♣. The general idea behind this system is to get the information about the shape of the hand across to partner in the first bid.
Inverted minors refers to a treatment introduced by the Kaplan–Sheinwold (K–S) bidding system for the popular card game bridge. The original structure of Precision, another bidding system, also employed inverted minors over a 1♦ opening. However, the treatment is no longer restricted to users of these bidding systems. although partnerships that use a Short club system tend also to use the convention only after a 1♦ opener.
New Minor Forcing (NMF), is a contract bridge bidding convention used to find a 5-3 or 4-4 major suit fit after a specific sequence of bids in which opener has rebid one notrump. The convention is triggered by responder at his second turn by an artificial bid of two in an unbid minor; it requires that he hold five cards in the major he has previously bid and an unlimited hand ranging in value from at least game invitational strength to that sufficient to have interest in slam; he may also hold four cards in the other major. Accordingly, there are six bidding sequences in which the New Minor Forcing bid may be applied:
Bridge base basic, also known as BBO basic, is a bidding system for the game of bridge based on the Standard American Yellow Card (SAYC). It is simplified, suitable for beginners, and widely used in internet bridge, particularly on Bridge Base Online. It is taught in Fred Gitelman's educational software called Learn to Play Bridge that is available as a free download from the American Contract Bridge League's website.
The Carrot 1NT is a contract bridge convention, in which a 1NT opening bid shows a balanced hand 13–17 HCP. With 13–14 HCP, the opener may not have a 4-card major. With 15–17 HCP, all balanced hands may be opened 1NT.
{{cite book}}: CS1 maint: location missing publisher (link); Conservation & Urban Design Team (February 2011). "South Hampstead Conservation Area (Formerly Known as Swiss Cottage Conservation Area) Character Appraisal and Management Strategy" (PDF). London Borough of Camden. p. 12, sec.4.9. Retrieved 15 January 2020.