The Baron bidding system was developed in the 1940s by Mr. Leo Baron and Mr. Adam Meredith, who was nicknamed Plum, and who was born in the year 1913 and died in the year 1976. Mr. Adam Meredith was a leading bridge personality of Britain, who was originally of County Down, Ireland.

Note: In his publication titled British Bridge Almanack (ISBN-13: 9780954924102) Mr. Peter Hasenson (Editor) includes the entry of Mr. Terence Reese, which is quoted below.

Date: mid-1930s. When I first played at Lederer's in the mid-1930s, Meredith was a handsome youth of 22, though he looked about 17... He was a marvelous player and did as much as anyone else to win the 1955 world championship match... He spent his last fifteen years or so in America, having formed a friendship with Ruth Sherman, who left him well provided for... It was not, perhaps, a satisfactory life for so brilliant and charming a person; but certainly it possessed colour, warmth and humour.

Note: Mr. Adam Meredith is the co-author with Mr. Leo Baron of the publication The Baron System of Contract Bridge, published in the year 1948. However, the Foreword to the publication, written by both Mr. Leo Baron and Mr. Adam Meredith, is dated 1st November, 1947. Publisher: Contract Bridge Equipment, Ltd., London, England, and printed by Henry Jenkinson Ltd.

Note: The picture of Mr. Adam Meredith presented below is one of the rare photographs of one of Britain's leading bridge personality. The date of the photograph is unknown.


Mr. Leo Baron

Very little information is available for Mr. Leo Baron, who was born in the country of Poland. According to the literature he made many important contributions to the bidding theory of the game of bridge. During his residence in England his victories at the bridge table include winning the Gold Cup in the year 1946 and also in the year 1951.

In the year 1952 Mr. Leo Baron emigrated to the country of Zimbabwe and took up residence in the city of Salisbury. The city was founded by Mr. Cecil Rhodes on September 12, 1890, as a military fort, and named after and for the 3rd Marquess of Salisbury (Robert Arthur Talbot Gascoyne-Cecil), who was at that time the British Prime Minister. The city of Salisbury was the capital of the Federation of Rhodesia and Nyasaland from 1953 to the year 1963. After 1963 the city was the capital of Southern Rhodesia.

Under the appointment of Mr. Ian Smith the move to declare the country of Rhodesia independent from the United Kingdom was successful on November 11, 1965. Mr. Leo Baron had lived in the country as a resident since 1951. On April 18, 1982 the name of the city Salisbury was changed permanently to Harare, which is a loan from the Shona Chieftain Neharawa.

Note: Review the bridge column of Mr. Alan Truscott of January 21, 1990, published in The New York Times. This article is only archived and preserved on this site in .pdf file format for future reference.

Note: the following presentation on this web page is only a summary of the highlights contained in his publication. For a more in-depth review of his concepts, principles, and approaches the reader is encouraged to read his publication.

Note: other excellent online sources can be found on the website of Michael Nistler and Simon's Conventions.


Note: The presentation below is from their mutual publication The Baron System of Contract Bridge, First Edition, published by Contract Bridge Equipment Ltd. of March 1948. The reader should read the following remembering that both authors had investigated the bridge principles, bridge philosophies, and bidding approach from the early years of the game to the year of their publication. It is upon this gathered and collected information that both authors published their conclusions. Everything after the year 1948 has no relevance.

The Structure of the System

The Baron system may be described briefly as strict Approach Forcing with the Four Trump Rule and the weak No Trump throughout" (i.e., vulnerable as well as non-vulnerable). The basic concept, as presented in the publication, is designed to give a general picture of the structure, with particular reference to Approach Forcing, the Four Trump Rule, limited bids and bidding sequences.

Note: when referring to bidding sequences both authors included in their system the principle that every (bidding) sequence should have one, and only one, meaning.

The system is described as an extremely natural system. The only conventional opening bid is Two Clubs, which does not indicate a Club suit. At the one level all bids and responses have their natural meaning, and this includes an opening bid of one Club. The Baron system does not employ a prepared Club. If the opening bid is 1 Club, then the partner assumes that partner has at least four Clubs unless and until the later rounds of the auction show that partner only holds three Clubs.

Note: A prepared Club is the same principle as the short Club or the convenient Club in an original opening bid on a three-card Club suit..

Approach Forcing: Before the publication of their Baron System in 1948 the authors concluded that the majority of the players employed a form of approach since the conviction of the bridge community believed that a slow exchange of information would result in a better result than by any other bidding method. The idea was to communicate as much information as possible via multiple bids in order to reach the most maximum and optimum contract, and thus the best score. The system of approach forcing was based at that time on the following definition as published in their book:

Approach methods are those by which the maximum amount of information is exchanged at the lowest possible level while ensuring that the bidding shall not die except in certain recognised ways.

As a result of this parameter and premise no player / partner, whose partnership agreement is based on the Baron system may pass only if his partner has made a limited bid. As long as neither partner has limited the holding, then no partner may pass to end the auction, but must keep the auction alive even if that partner holds minimum values. An example of this approach forcing is presented below to illustrate this most important point of the Baron system.

South   West   North   East
1   Pass   1   Pass

The conclusion of both authors by this bidding sequence is that North normally would pass the 2 Clubs rebid by the South. However, since the approach forcing requires a second bid by North, then the more appropriate first response by North should be 1 No Trump, which limits the values of the holding.

The Four Trump Rule

Mr. Leo Baron and Mr. Adam Meredith both concluded that support should always show at least four cards. It was the general acceptance of the fact that seven trumps does not constitute a playable suit. Adherence to this principle of the Four Trump Rule reduces the number of possible bids in any given situation that partner can nearly always tell, from the actual sequence used, what the shape and strength of the holding is. Both authors calculated that those players, who indeed use the Four Trump Rule in certain situations only lose nine-tenths of its value.

The following two examples illustrate the principle behind the Four Trump Rule.

Example 1
South   West   North   East
1   Pass   2   Pass
Hand 1
Example 2
South   West   North   East
Hand 2

By this sequence the opener guarantees a five-card Spade suit with Hand 1. The opener cannot have fewer than five Spades because the opener would have then opened the auction with 1 Club, as in Hand 2.

Example 2
South   West   North   East
1   Pass   2   Pass

Normally this sequence is very similar to the above example. In most instances the opener will hold at least five Hearts because with only four Hearts the opener would open with 1 Club.

There is, however, one case when the opener will have only four Hearts, namely when the holding is 4-4-4-1 with a singleton in Spades as in Example 2.When this is the case, then the opener bids 1 Hearts first, and over a two Clubs response the opener raises to three Clubs.. If the responder makes an effort for game by bidding three Hearts, which requests that the opener to bid game in Hearts if he holds a five-card suit. The opener, with a 4-4-4-1 pattern, denies holding a five-card suit by bidding four Clubs, which thereby automatically shows the exact distribution.

Limited Bids

The definition of a limited bid is that it represents a bid, which conveys the value of the hand within definite and defined limits, and, as such, may therefore be passed. The Baron system defined any such bid in a distinctive and narrow fashion. For any limited bid to have any values the bid may not overlap in the established ranges. There was no demarcation of the limited bid whether the limit bid was employed as a direct raise, the rebid of a suit, or any No Trump bid.

The definition of the limit bid and the use of a comprehensive series of limited bids is essential to the successful use of Approach methods since the one is the complement of the other. The reasoning of both authors is that when every change of suit is forcing it would be impossible to stop if the players did not take the opportunities that present themselves of making a limited bid.

Bidding Sequences

The entire structure of the Baron system is built around the idea that a bid can only be interpreted in the light of the whole auction. Therefore, as both authors conclude, if the previous auctions are slightly different the same bid in those auctions may have a different meaning. Both authors stress and emphasis is laid on the entire sequence rather than on any isolated bids.

According to the account of the authors there is no department in which inferences from the early auction can be of greater value than in slam bidding, because one of the most serious stumbling blocks to accuracy in slams is the wasted value (for example, KJx opposite a singleton). If a player can be certain of partner's exact distribution it becomes a simple matter to decide which cards are valuable and which are likely to be wasted.

The success of the Baron bidding system has lead to the incorporation of many treatments and conventions into the Acol bidding system. Only the main features of the Baron bidding system and not the complete system is presented.

Several features of the Baron System include:
1. The Weak No Trump opening bid combined with a No Trump constructive rebid.
2. Bidding up the line with 4-card suits.
3. Relaxed requirements for biddable suits.
4. The 5-card suit requirement for a response of 2 Hearts to an opening of 1 Spade.
5. The lead of the Ace from Ace-King.
6. The bid of the third suit by the opener on the one level is a forcing bid. Some players include this requirement on the two level.
7. An immediate raise requires at least a 4-card trump support.
8. Suit opening bids are highly prepared, with a 4-card Spade suit being opened ahead of a 5-card Heart suit regardless of the quality of the suit.
9. Simple overcalls are strong and jump overcalls are weak.

Baron Slam Try

The Baron Slam Try is an invitation to a slam contract if the partner holds good trump support. A bid of the suit next below the agreed suit at the five or six level specifically asks partner whether he holds good trump support or not. For example:

1. If Spades is the agreed suit, then 5 Hearts invites to 6 Spades.
2. If Spades is the agreed suit, then 6 Hearts invites to 7 Spades.
  Note: Each partner must consider the information shared in the continuing auction and decide what constitutes good trump support.

Baron Response of Two No Trump after an Opening Suit Bid of One

This feature of the Baron Slam Try indicates 16-18 high card points and is game forcing. In the regular Baron bidding system, the responses of 2 No Trump and 3 No Trump are inverted.

The inversion bid of 3 No Trump equals 12-14 high card points, and the effect is that the opener can select a suitable game contract.
The 2 No Trump response leaves more bidding space open for exchanging descriptive information about the holdings where a slam contract is a feasible possibility.

Note: The Acol bridge player, and especially those bridge players learning the Baron bidding system must be acutely aware of the distinction between the Baron bidding system and the Baron convention. The Baron convention only refers to the feature of asking for a 4-card suit following a strong, artificial 2 Clubs opening bid followed by a 2 No Trump rebid. The two have become somewhat interchangeable within the Acol bridge community.

Note: According to several authored bridge-related publications, also online, the general conclusion in the Acol-world is as follows: Although the Baron System is presently defunct, the Baron System had developmental and historical significance. The Baron System placed more emphasis on constructive bidding than did the Acol system of that time, and extended the 'change of suit forcing' idea. This influenced the development of later versions of the Acol system. In addition, the Baron System incorporated a 1 No Trump overcall as a weak distributional take-out bid.



If you wish to include this feature, or any other feature, of the game of bridge in your partnership agreement, then please make certain that the concept is understood by both partners. Be aware whether or not the feature is alertable or not and whether an announcement should or must be made. Check with the governing body and/or the bridge district and/or the bridge unit prior to the game to establish the guidelines applied. Please include the particular feature on your convention card in order that your opponents are also aware of this feature during the bidding process, since this information must be made known to them according to the Laws of Duplicate Contract Bridge. We do not always include the procedure regarding Alerts and/or Announcements, since these regulations are changed and revised during time by the governing body. It is our intention only to present the information as concisely and as accurately as possible.


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