A bidding system in

contract bridge Contract bridge, or simply bridge, is a trick-taking card game using a standard 52-card deck. In its basic format, it is played by four players in two competing partnerships, with partners sitting opposite each other around a table. Millions o ...

is the set of

agreements Agreement may refer to: Agreements between people and organizations * Gentlemen's agreement, not enforceable by law * Trade agreement, between countries * Consensus, a decision-making process * Contract, enforceable in a court of law ** Meeting of ...

and understandings assigned to calls and sequences of calls used by a

partnership A partnership is an arrangement where parties, known as business partners, agree to cooperate to advance their mutual interests. The partners in a partnership may be individuals, businesses, interest-based organizations, schools, governments o ...

, and includes a full description of the meaning of each treatment and convention. The purpose of bidding is for each partnership to ascertain which contract, whether made or defeated and whether bid by them or by their opponents, would give the partnership their best scoring result. Each bidding system ascribes a meaning to every possible call by each member of a partnership, and presents a codified language which allows the players to exchange information about their card holdings. The vocabulary of is limited to 38 different calls - 35 level/denomination ''bids''A bid consists of two components — the level in range of 1-7, and one of five denominations: clubs (), diamonds (), hearts (), spades () and notrump (NT) plus ''pass'', ''double'' and ''redouble''. Any bid becomes a contract if followed by three successive passes, therefore every bridge bid is a potential contract. By the rules of the game, the agreed meanings of all calls must be public and known to the opponents. In normal club or home play, the opponents are entitled, at their turn to make a call, to ask the partner of the bidder about the meaning of the call. In high-level tournaments, where

screens Screen or Screens may refer to: Arts * Screen printing (also called ''silkscreening''), a method of printing * Big screen, a nickname associated with the motion picture industry * Split screen (filmmaking), a film composition paradigm in which m ...

are used, the procedure is to ask the screen-mate about their calls as well as their partner's calls. In serious online tournaments, the procedure is for the player making the call to self-alert it, but the explanation is visible only to the opponents.

Classification

Bidding systems can be classified into two broad categories: ''natural'' systems and ''artificial'' systems. In natural systems, most bids (especially in the early phase of the bidding) denote length in the suit bid. In artificial systems, the bids are more highly codified, so that for example a bid of 1 may not be related to a holding in the club suit. Natural system(s) are the "

lingua franca A lingua franca (; ; for plurals see ), also known as a bridge language, common language, trade language, auxiliary language, vehicular language, or link language, is a language systematically used to make communication possible between groups ...

" of bridge players, with regional variations. Thus, a new partnership can agree to play a natural system and understand each other fairly well. Players sometimes alter certain aspects of a system, adding their specific agreements or preferred conventions. Structure and meaning of opening bids are the common determining factor for system classification: in most modern natural systems, opening bids of 1 through 2 have the same or similar meaning, with level-one bids denoting length in a suit. Artificial systems typically reserve at least one one-level suit opening bid for special purposes, unrelated to the suit.

Natural systems

Natural systems generally use opening bids as follows: *A bid of 1 or 1 shows at least 4 or 5 cards in the

major suit In the card game contract bridge, the major suits are spades () and hearts (). The major suits are of prime importance for tactics and scoring as they outrank the minor suits while bidding and also outscore them (30 per contracted trick for major ...

, and 1 or 1 shows at least 3 or 4 cards in the

minor suit In contract bridge the minor suits are diamonds () and clubs (). They are given that name because contracts made in those suits score less (20 per contracted trick) than contracts made in the major suits (30 per contracted trick), and they rank lo ...

. The complete hand usually contains about (11)12-20(22)

high card points In contract bridge, various bidding systems have been devised to enable partners to describe their hands to each other so that they may reach the optimum contract. Key to this process is that players evaluate and re-evaluate the trick-taking pot ...

. As between two major suits or between two minor suits, the bidder opens in the longer suit; with equal lengths, the higher ranking suit is usually chosen. If the opening bid of 1 or 1 promises 5 cards, the system is referred to as a " five-card major" system; otherwise, it is referred to as a " four-card major" system. The term ''five-card majors'' implies that an opening bid in a minor suit bid might show three card length only (for example, the hand pattern might be 4=4=2=3, so neither major suit is long enough to show with an opening bid). *A bid of 1NT shows a balanced hand in a narrow

(HCP) range. The common ranges are 15-17 or 16-18 HCP (" strong notrump") and 12-14 (" weak notrump"). *A bid of 2 typically shows a very strong hand (22+ points). *A bid of 2NT shows a strong balanced hand, usually 20-21 HCP. *Opening bids of 3 of any suit are

preempt Preempt (also spelled "pre-empt") 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 ...

ive, showing a 7+ card suit and 6-10 points (mostly inside the bid suit). *The meaning of 2, 2 and 2 varies. One common usage is that the bid shows a

weak two bid The weak two bid is a common used in the game of contract bridge, where an opening bid of two diamonds, hearts or spades signifies a weak hand, typically containing a long suit. It may be deployed within any system structure that offers a forcing ...

, similar to a

ive bid. Another is the

strong two bid In contract bridge, a strong two-bid (also known as a forcing two-bidFrancis et al (2001), p. 443.Francis et al (2001), p. 163. The strong two-bid was the cornerstone of the Culbertson system.) is an opening bid of two in a suit, i.e. 2, 2, 2 or ...

, which is natural and shows a very strong hand (too strong for a 1-level opening). Yet another usage, popular in otherwise natural systems, is to use weak two bids in the major suits, and 2 as

Flannery Flannery is a bridge convention using a 2 opening bid to show a hand of minimal opening bid strength (11-15 high card points) with exactly four spades and five (or sometimes six) hearts. It was invented by American player William (Bill) L. Flanne ...

: four spades and five hearts in a hand of minimum strength.

Specific systems

The most widespread natural systems are: *

Acol Acol is the bridge bidding system that, according to ''The Official Encyclopedia of Bridge'', 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, ...

, featuring 4-card majors and weak notrump, originating in Great Britain *

Standard American Standard American is a bidding system for the game of bridge widely used in North America and elsewhere. Owing to the popularization of the game by Charles Goren in the 1940s and 1950s, its early versions were sometimes referred to simply as 'G ...

, originally with 4-card majors but later adopting 5-card majors. Strong notrump. *

Bridge Base Basic 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 On ...

, based on Standard American and used in internet play * 2/1 game forcing, based on Standard American and gradually superseding it. Some features of ''2/1 game forcing'' originated from the Roth–Stone and

Kaplan–Sheinwold The Kaplan–Sheinwold (or "K-S") 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 defini ...

systems of the 1950s and 1960s. Various developments in the area of natural systems have resulted in systems that are natural in essence, but contain special features. Examples are systems like Romex, Boring Club, Fantunes, and EHAA (Every Hand An Adventure).

Artificial systems

Artificial systems can be further classified into: * Strong club systems are the most popular artificial systems, where opening of 1 shows a strong hand (typically 16+ HCP). Other 1-level bids are typically natural, but limited to about 15 HCP. The most popular strong club systems are: **

Vanderbilt Club Vanderbilt Club was one of the earliest bidding systems in the game of contract bridge. It was devised by Harold S. Vanderbilt, who had in 1925 devised the game itself. It was published by him in 1929. It was the first strong club system. An up ...

(the predecessor) **

Precision Club Precision Club is a bidding system in the game of contract bridge. It is a strong club system developed in 1969 for C. C. Wei by Alan Truscott, and used by Taiwan teams in 1969. Their success in placing second at the 1969 Bermuda Bowl (and Wei's ...

** Blue Club *In Small club systems, the opening bid of 1 is forcing but not necessarily strong. It typically includes some range of balanced hands, some hands with long club suit, and very strong hands. Examples are: ** Vienna System (the predecessor) **

Roman Club Roman Club ( it, Fiori Romano) is an artificial bridge bidding system devised in the 1950s by Giorgio Belladonna and Walter Avarelli of Italy's Blue Team. They used it to win twelve WBF World Teams Championships, three Olympiads and numerous Eu ...

, developed and used by famous Blue Team ** Polish Club, originating (and standard) in

Poland Poland, officially the Republic of Poland, is a country in Central Europe. It is divided into 16 administrative provinces called voivodeships, covering an area of . Poland has a population of over 38 million and is the fifth-most populous ...

but also gained certain popularity worldwide. ** Dutch doubleton, an offspring of the Polish Club system ** SAYC+, Based on Standard American but with the 1 forcing and including all 21+ hands too

*Strong diamond systems are similar to strong club systems, but the bid of 1 shows a strong opening, typically 16+ and the bid of 1 is typically nebulous. This gives more room over the nebulous 1 opening compared to the strong club's nebulous 1 opening. There are several examples listed her
www.strongdiamond.co.uk
* Strong pass systems are based on the idea that 8-12 HCP hands are the most frequent (about 45% chance to hold such a hand). Most of the initial opening bids describe this range, while strong (13+ HCP) hands (28% of the hands) start with PASS, the lowest available call. Weak (0-7 HCP) hands are opened with one other bid, often 1. Of course partner in 3rd or 4th place will never pass a strong PASS "opening", thus 3rd and 4th place "openings" are different. Strong pass systems were popular in Poland in the 1960s and 1970s, before the restrictions. These systems are often relay-based, but it is not a necessity, their main advantage is that they initiate with the most frequent intermediate hands and rob some bidding space with the weak ones.
Strong pass systems are mostly banned by World Bridge Federation and other governing organizations from all competitions except the highest-level ones, because opponents cannot be reasonably expected to cope with such an unusual approach. ''See:

Highly unusual method Highly unusual methods (also HUM) is a class of contract bridge bidding system A bidding system in contract bridge is the set of Glossary of contract bridge terms#agreement, agreements and understandings assigned to Glossary of contract bridge t ...

'' *Relay systems are based on

relay bid In contract bridge, a relay bid is a conventional bid that usually has little or no descriptive meaning but asks partner to describe some feature of his hand. A relay is often the cheapest bid available but need not be. Stayman and Blackwood ...

s – the artificial bids where one partner just bids the cheapest denomination (''relay bid'') and the other describes his distribution and high cards in detail (''relay response'') using a highly codified scheme. Such systems are out of the above classification (based on opening bid structure), as the relay feature takes place later in the auction. For example, relatively popular "Moscito system" has variants based o
strong-club
and

approaches

is based on Precision club. Relay systems do not need to begin with an initial forcing pass or an initial forcing 1 opening. The ACBL typically disallows relay systems, on the grounds that they are too difficult to defend against without a lot of advance preparation.

Notes

External links