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Number of Players	Number of Cards	Game Play	Skill Level
4	52	Easy - Complex	Luck - Skill

Since the 1930s, Contract Bridge has been one of the most popular card games in the world. Today, perhaps only Poker has more participants. Countless newspapers have daily Bridge columns, and there are more books about Bridge than any other game, except Chess. Bridge tournaments continue to attract thousands of players who compete with each other to become Life Masters.

The game of Whist appeared in England in the 1600s. The game developed into Bridge (1894), then Auction Bridge (1903), and finally the American form of Contract Bridge (1925). Whist and Auction Bridge still have followers, but Contract Bridge has become the most popular of these games.

Contract Bridge is an ideal game for entertainment because it is a partnership game. It is ideally adapted for social play at home or at clubs that meet weekly in groups of eight, 12, or more. Finally, the game is wonderful for tournament play among serious players.

A fascinating feature of Contract Bridge is that it is enjoyed equally by casual players, who do not want to take any game too seriously, and by scientific players who wish to study and master the intricacies of complex bidding techniques and card-play strategies.

The rules of Contract Bridge are presented here. These are condensed from The Laws of Contract Bridge copyright The American Contract Bridge League. For those who wish to learn the game on a more advanced level, there are hundreds of books and professional teachers.

Object of the Game. Each partnership attempts to score points by making its bid (or contract), or by setting (defeating) the opposing partnership's bid. At the end of play, the side with the most points wins, and the difference in points between the two partnerships is the margin of victory.

Preliminaries
Number of Players. Four people play, as partners, two against two. (Five or six people may take part in the same game by "cutting in"; that is, one or two players sit out for a set of deals while the other four are playing.) For ease of discussion, the positions of the four players at the table correspond to the compass points, North, South, East and West, with North and South playing as partners against East and West. In the scoring, partners share equally in every result so that only one score is kept for each side.

The Pack. The standard 52-card pack is used. Players usually have two packs with contrasting back designs. While one pack is being dealt, the dealer's partner shuffles the other pack for the next deal.

Rank of Suits. Spades (high), hearts, diamonds, clubs.

Rank of Cards. A (high), K, Q, J, 10, 9, 8, 7, 6, 5, 4, 3, 2.

The Draw. Any player spreads a shuffled pack face down on the table and each player draws one card, but not one of the four cards at either end of the spread. (A player who exposes more than one card must draw again.)

The player drawing the highest card deals first. That player chooses his seat and the pack with which he will deal; the next highest card designates that player's partner who sits directly across the table. The two others take the remaining two seats. If two players draw cards of the same rank, such as 8 and 8, the rank of the suits determines the higher card; thus, in this example, the 8 would win the draw.

The Shuffle. The player to the dealer's left shuffles the cards and places them on the dealer's left. The dealer (after shuffling again, if he desires) sets the cards down on the right to be cut.

The Cut. The player at dealer's right must lift off a portion of the pack (not fewer than four cards nor more than 48) and set it down toward the dealer. The dealer completes the cut.

The Deal. The dealer distributes 13 cards to each player, one card at a time, face down, beginning with the player on his left.

Rotation. The turn to deal, to bid, and to play always passes to the left, from player to player. For example: If South is the dealer for the first hand, then West will deal next, then North, then East, and then South again. Likewise, in the play, if North leads a card, then East will play next, then South, and then West.

 

VANDERBILT'S CLAIM TO FAME Many card games have evolved gradually, and no specific date can be given for the inception of some games. However, the invention of Contract Bridge can be dated with certainty: November 1, 1925. The inventor was the famous yachtsman Harold S. Vanderbilt, and he recorded the game’s inception this way:"I compiled in the autumn of 1925 a scoring table for my new game. I called it Contract Bridge and incorporated . . . a number of new and exciting features; premiums for slams bid and made, vulnerability, and decimal system of scoring . . . . An ideal opportunity to try out my new game presented itself while I was voyaging . . . . on board the steamship Finland from Los Angeles to Havana via the Panama Canal."

The Bidding
Calls. Once the cards are dealt, each player picks up his hand. It is common for a player to arrange his hand into suits and further arrange each suit into descending order. Each player fans his hand to see all the cards, and keeps his fanned hand close enough to him so that no other player can see his cards. The auction or bidding then begins: Each player in rotation, beginning with the dealer, makes a call (pass, bid, double or redouble).

Passing. When a player does not wish to bid, to double, or to redouble, he says, "Pass." If all four players pass in the first round, the deal is "passed out," and the next dealer in turn deals a new hand.

Bidding a Suit. Each bid must name a certain number of tricks in excess of six (called "odd-tricks") that the bidder contracts to win, and a suit which will become the trump suit, if the bid becomes the final contract. Thus, One Spade is a bid to win seven tricks (6+1) with spades as trumps, and Four diamonds is a bid to win 10 tricks (6+4) with diamonds as trumps. A bid may be made in Notrump, meaning that there will be no trump suit. The lowest possible bid is one, and the highest possible bid is seven.

Each bid must name a greater number of odd tricks than the last preceding bid, or an equal number but in a higher denomination. Notrump is the highest denomination, outranking spades. Thus, a bid of Two Notrump will overcall a bid of Two Hearts, and a bid of Four Clubs is required to overcall a bid of Three Notrump.

Doubling and Redoubling. Any player in turn may double the last preceding bid if it was made by an opponent. The effect of a double is to increase the value of the points at stake if the doubled bid becomes the contract. (See Scoring Table, page 10.)

Any player in turn may redouble the last preceding bid if it was made by his side and doubled by an opponent. A redouble again increases the scoring values.

A doubled or redoubled contract may be overcalled by any bid which would have been sufficient to overcall the same contract undoubled. Thus, if a bid of "Two Spades" is doubled and redoubled, it may still be overcalled by a bid of "Two Notrump," a bid of "Three Clubs," or by any other higher bid.

Final Bid and the Declarer. When a bid, double, or redouble is followed by three consecutive passes in rotation, the bidding is closed. The final bid in the auction becomes the contract. The player who, for his side, first bid the denomination named in the contract becomes the "declarer." If the contract names a trump suit, every card of that suit becomes a trump. The declarer's partner becomes the "dummy," and the opposing players become the "defenders."

The Play
Leads and Plays. A play consists of taking a card from one's hand and placing it, face up, in the center of the table. Four cards so played, one from each hand in rotation, constitute a trick. The first card played to a trick is a lead.

The leader to a trick may lead any card. The other three hands must follow suit if they can. If a player is unable to follow suit, he may play any card.

For the first trick, the defender on the declarer's left makes the first lead (the opening lead).

Facing the Dummy Hand. As soon as the opening lead has been made, the dummy then spreads his hand face up, grouped in suits, with each suit vertically arranged so that the other three players can easily view all 13 cards. The suits may be placed in any order as long as the trump suit (if any) is placed to the declarer's left. There is no particular order for placing the suits down in a Notrump bid.

Winning of Tricks. A trick containing a trump is won by the hand playing the highest trump. A trick not containing a trump is won by the hand playing the highest card of the suit led. The winner of each trick leads next.

Declarer's Play. The declarer plays his own cards and the dummy's cards, but each in proper turn, since the dummy does not take an active part in the play.

Played Card. The declarer plays a card from his own hand when he places it on the table or when it is named as an intended play. When the declarer touches a card in the dummy hand, it is considered played (except when he is merely arranging the dummies cards). Alternatively, the declarer may name a card in the dummy and such a card must be played. A defender plays a card when he exposes it so that the other defender can see its face. A card once played may not be withdrawn, except to correct a revoke or other irregularity.

Taking in Tricks Won. A completed trick is gathered and turned face down on the table. The declarer and one of the defenders should keep all tricks won in front of them, and the tricks should be arranged so that the quantity and the order of the tricks played are apparent.

The Scoring
When the last (13th) trick has been played, the tricks taken by the respective sides are counted, and the points earned are then entered to the credit of that side on the score sheet. Any player may keep score. If only one player keeps score, both sides are equally responsible to see that the score for each deal is correctly entered.

The Scoring Table on page 10 indicates the point values, and a sample score sheet appears on page 9. The score sheet is ruled with a vertical line making two columns that are headed We and They. The scorekeeper enters all scores made by his side in the We column and all scores made by the opponents in the They column. A little below the middle of the score sheet is a horizontal line. Scores designated as "trick score" are entered below the line; all other scores are "premium scores" and and are written above the line.

Trick Score. If the declarer fulfills his bid by winning as many or more odd-tricks as the contract called for, his side scores below the line for every odd-trick named in the contract. Thus, if the declarer wins eight tricks and the bid is Two Hearts, the score for making "two" in a bid of hearts would be credited, as per the Scoring Table.

Overtricks. Odd-tricks won by the declarer in excess of the contract are called "overtricks" and are scored to the credit of his side as premium score.

Game. When a side has scored 100 or more points below the line, it has won a "game." To show this, the scorekeeper draws a horizontal line across the score sheet, below the score which ended the game. This signifies that the next game will begin. A game may be made in more than one deal, such as by scoring 60 and later 40, or it may be scored by making a larger bid and earning 100 or more points in a single deal. Once the next game begins, if the opponents had a score below the line for making a bid, such as 70, this score does not carry over, and each side needs the full 100 points to win the next game.

 

THE BARON PONDERS FOR TWO HOURS Waldemar von Zedtwitz was considered by many to be the greatest player of the 1930s and '40s."The Baron" was a very wealthy man, but he often wore the same light gray cotton cord suit for days at a time. As the declarer he was extremely slow in his card play, often tugging at his ear or a tuft of hair as he concentrated intensely. One day while dining alone in a fine restaurant in Manhattan, von Zedtwitz was pondering deeply about a Bridge hand that he had played some 35 years before. After some two hours, the check was still face down at his table, and the nearby waitresses were beginning to think that maybe this simply dressed man could not afford to pay the tab. Eventually, the employees took up a collection and one of the waitresses placed the money discretely on his plate on top of the check. The Baron finally snapped out of his stupor and put an equal amount of money on the plate- plus an exorbitant tip-and ambled out of the restaurant, still in deep concentration.

Vulnerable. A side that has won its first game becomes "vulnerable," and that side's objective is to win a second game and thus earn a bonus for the "rubber." When a side scores its second game, the rubber is over, and the scores are totaled. The winning partnership is the side with the most points. A vulnerable side is exposed to increased penalties if it fails to fulfill a future bid, but receives increased premiums for certain other bids that are fulfilled.

Honors. When there is a trump suit, the ace, king, queen, jack, and ten of trumps are "honors." If a player holds four of the five trump honors, that partnership scores 100 above the line; all five honors in one hand score 150. If the contract is in Notrump, a player holding all four aces scores 150 above the line for his side. Note that the points for honors are the same whether the side is not vulnerable or vulnerable, and that the defenders can also score for honors.

Slam Bonuses. Other premium scores are awarded for bidding and making a "small slam" (a bid at the six-level, such as Six Hearts) or a "grand slam" (a contract at the seven-level, such as Seven Spades or Seven Notrump).

Doubled or Redoubled Contract. When the declarer makes a doubled contract, a premium bonus is scored. Making a redoubled contract scores an even bigger premium bonus - this is a recent change in scoring. Note that doubling and redoubling do not affect honor, slam, or rubber bonus points.

Unfinished Rubber. If the players are unable to complete a full rubber and only one side has a game, that side scores a 300 bonus. If only one side has a part score, that side earns a 100 bonus.

Back Score. After each rubber, each player's standing, plus (+) or minus (-), in even hundreds of points, is entered on a separate score called the "back score." An odd 50 points or more count 100, so if a player wins a rubber by 950 he is +10, if he wins it by 940 the player is +9.

Bridge for Five or Six Players. When five people wish to play, the draw for deal establishes the order of precedence, and the player drawing the lowest card sits out for the first rubber. After the first rubber the fifth player joins the game, and the player who drew the fourth highest card sits out. After the next rubber, the player who just sat out re-enters the game, and the player who drew the third highest card now sits out, and so on until all players have sat out a rubber, after which the fifth player sits out again. The procedure is similar with six players, except that two sit out each rubber. Since a rubber can be any number of hands from two to twenty or more, a good variant is Four-Deal ("Chicago") Bridge, which is explained on page 12.

Illustration of Contract Bridge Scoring

a) WE bid Two Hearts and win nine tricks, scoring 60 points below the line (trick-score) for 2 tricks at hearts bid and made (30 each), and 30 points above the line (premium-score) for 1 over-trick at hearts. WE now have a part-score of 60 toward game.

b) WE then bid Two Clubs and make four-odd, scoring 40 points trick-score for 2 tricks bid and made (20 each), completing our game (100 points). So now, a line is drawn across both columns to show the end of first game of the rubber. WE also score 40 points for 2 overtricks at clubs (20 each), and 100 points for four honors in one hand (one of us held A K J 10). WE are now vulnerable.

c) WE bid Four Hearts, are doubled and set one trick as we make only 9 tricks. Our opponents score 200 for defeating our contract because WE are vulnerable.

d) The opponents bid Four Spades but win only 9 tricks; THEY are set 1. WE score 50 points, because THEY are not vulnerable and WE did not double. One of them held A Q J 10, so they score 100 points for honors even though THEY did not make their contract.

e) WE bid and make One Notrump. This scores 40 points for us below the line. WE need only 60 points more to make a game

f) THEY bid and make Three Notrump, scoring 40 for the first trick, 30 for the second trick and 30 for the third trick over six (100 points below the line), and win a game. Another horizontal line is drawn across both columns, marking the end of the second game. Our part-score can no longer count toward a game. Now both sides are vulnerable.

g) WE bid Two Spades and are doubled. WE are set 3 tricks as WE won only 5 tricks, and the opponents hold 100 honors as well. THEY score 800 for the set and 100 for the honors.

h) WE bid and make Six diamonds, a small slam, scoring 120 points trick-score (below the line), 750 bonus for a little slam, and 500 for winning the rubber as premium score above the line. Adding the score for both sides, WE have 1730 points, THEY 1300; WE win the rubber by 430. This gives us a 4-point rubber (see "Back Score," page 8).

 

THE DUKE OF CUMBERLAND IS FLEECED FOR £20,000!       Final contract: Seven Clubs Redoubled, played by South Opening lead: Jack of Hearts This is likely the most famous hand in the history of bridge, although it was actually first reported in a game of Whist. The story has it that the Duke of Cumberland (son of King George III) some 200 years ago held the East hand. The wager from his opponents was that in spite of the duke’s incredible hand, he would not win a single trick against a contract of Seven Clubs redoubled. The bet was some £20,000, and, alas, the duke lost his wager for the grand slam cannot be defeated if the declarer plays correctly. Assuming that West’s opening lead is a diamond or a heart, the declarer trumps, ruffs a spade in dummy, and then returns a club for a successful finesse against East. Now the declarer ruffs another spade in dummy, takes another successful trump finesse, and ruffs a third round of spades in dummy. His remaining spades are now established, and he returns to his hand by trumping a diamond or a heart. After cashing the ace of trumps,

Four Deal Bridge
(Chicago)
This version uses the same rules and, with exceptions noted below, the same scoring as standard Contract Bridge. In a cut-in game with five or six players, a player who is "cut out" often has a long wait until the rubber ends and he can re-enter. By playing Four-Deal Bridge, a player seldom has to wait more than 15 or 20 minutes. The game is often called Chicago because it originated at the Standard Club in Chicago.

A round consists of four deals, one dealt by each player in turn. Vulnerability for a side is determined by which deal is being played, as follows:

First deal: Neither side is vulnerable.

Second and third deals: The dealer's side is vulnerable and opponents are not vulnerable. Even if the opponents previously made game, it does not matter.

Fourth deal: Both sides are vulnerable.

A passed-out deal is redealt by the same dealer. There is a bonus, scored immediately, of 300 for making game when not vulnerable and 500 when vulnerable. A part-score carries over as in Rubber Bridge and can help to make game in the next deal or deals, but it is canceled by any game score. There is a bonus of 100 for making a part-score on the fourth deal. After four deals have been played, the scores are totaled and entered on the back score, as in Rubber Bridge, and there is a new cut for partners, seats, and deal.

In one variation, played in certain regions, on the second and third deals the dealer's side is not vulnerable and the opposing side is vulnerable instead.

More points are usually scored in Four-deal Bridge than in the same number of deals at Rubber Bridge - estimates vary from 15 percent to 40 percent more. This is chiefly because at least one side is vulnerable in three deals out of four.

Standard Contract Bridge Bidding
The main parts in a game of Contract Bridge are the bidding and play. To bid correctly, a player should first determine the value of his hand and then state the bid consistent with that value. There are various systems of hand-valuation. The easiest and most popular one used in America is the "Point-Count System" advocated by Charles H. Goren, one of the great tournament champions and the player who is credited with popularizing Bridge in the 1950s. A modified outline of this system follows. It comprises the point-count method for hand-valuation and the requirements needed for various bids.

(A section on suggested leads in the play of the hand follows on page 21.)

Standard (Goren) Point-Count Table
High-Card Points
Ace = 4 points
King = 3 points
Queen = 2 points
Jack = 1 point

High-card points (usually called simply "points") are counted for nearly every bid. Distributional points, described below, are often added to high-card points to get a more accurate measure of just what a hand is worth.

Game and Slam Requirements Usually 26 points will produce a game, 33 points will produce a small slam, and 37 points will produce a grand slam.

Distribution Points
The Opening Bidder Counts -
Void suit (no cards in suit) = 3 points
Singleton (1 card in suit) = 2 points
Doubleton (2 cards in suit) = 1 point
Add 1 point for all 4 aces. Deduct 1 point for an aceless hand. Deduct 1 point for each unguarded honor. Example: Q-x, J-x, singleton K, Q, or J.

Opening Bid Requirements

One of a suit	14-point hands should be opened; 13-point hands may be opened if a good rebid is available (a rebiddable suit or a second biddable suit). A third-position opening is permitted with 11 points if hand contains a good suit. Minimum biddable suit: Q-x-x-x, or any five-card suit (x-x-x-x-x).
Two of a suit	25 points with a good 5-card suit; 23 points with a good 6-card suit; 21 points with a good 7-card suit.
Three, four, or five of a suit (preemptive bids)	Preemptive bids show less than 10 points in high cards and the ability to win within two tricks of the bid when vulnerable and within three tricks when not vulnerable. They should usually be based on a good seven-card or longer suit.
One Notrump	16 to 18 points (in notrump bidding only high-card points are counted) and 4-3-3-3, 4-4-3-2 or 5-3-3-2 distribution with Q-x or better in any doubleton.
Two Notrump	22 to 24 points and all suits stopped.
Three Notrump	25 to 27 points and all suits stopped.

Choice of Suits. Generally speaking, a player should bid his longest suit first. With two five-card suits, he should bid the higher ranking first. With two or more four-card suits, he should bid the suit immediately lower in rank to his short suit (doubleton, singleton, or void).

Five-Card Majors
In many rubber Bridge games and in standard American tournament play, an opening bid of 1 or 1 guarantees at least a five-card suit. This information is very helpful to the responder who can support the suit with as few as three small cards - or even a doubleton headed by a jack or better. With ample points for an opening bid and no five-card major or suitable holding for 1NT, the player opens 1 or 1, whichever minor suit is longer - even if there are only three cards in the suit. Even though the opening bidder bids a three-card suit, the contract will rarely be passed out at this low level, and if it is, it is probable that the opponents could have bid and made a higher contract of their own. An opening bid of 1 or 1 requests the partner to bid a major suit (hearts or spades) if he has one.

Responses
Any bid of a new suit by the responding hand is forcing on the opening bidder for one round. Thus, each time the responder bids a new suit, the opener must bid again. If responder should jump, the bid is forcing to game.

With fewer than 10 points, the responder should prefer to raise partner if the latter has opened in a major suit, and to bid a new suit himself at the one level in preference to raising a minor-suit opening bid. With 11 or 12 points, the responder can make two bids but should not force to game. With 13 points or more, the responder should see that the bidding is not dropped before a game contract is reached. With 19 or more points, he should make a strong effort to reach a slam.

Responses to Suit-Bids of One. Raise. When raising a partner's suit, count 5 points for a void, 3 for a singleton and 1 for a doubleton. To raise a partner's suit the responder must have adequate trump support. This consists of J-x-x, Q-x-x, x-x-x-x, or better for a non-rebid suit; and Q-x, K-x, A-x, or x-x-x for a rebid suit.

Raise partner's suit to two with 7 to 10 points and adequate trump support.

Raise to three with 13 to 16 points and at least four trumps.

Raise to four with no more than 9 high-card points plus at least five trumps and a short suit (singleton or void).

Bid of a new suit. At the one-level this bid requires 6 points or more. This response may be made on anything ranging from a weak hand, when a responder is just trying to keep the bidding open, to a very powerful one, when the responder is not sure where the hand should be played. At two-level a bid requires 10 points or more.

A jump in a new suit requires 17 points or more (the jump shift is reserved for hands when a slam is very likely. Responder should hold either a strong suit or strong support for the opener's suit).

Notrump responses (made with balanced hands). A 1NT response 6 to 9 points in high cards. (This bid is often made on an unbalanced hand if the responder's suit is lower in rank than the opening bidder's and the responder lacks the 10 points required to take the bidding into the two level.) A response of two - 2NT - requires 13 to 15 points in high cards, all unbid suits stopped, and a balanced hand. A response of three - 3NT requires 16 to 18 points in high cards, all unbid suits stopped, and very balanced distribution.

Responses to Suit-bids of Two. An opening bid of two in a suit (such as Two Hearts) is unconditionally forcing to game and the responder may not pass until game is reached. With 6 points or less the responder bids 2NT regardless of distribution. With 7 points and one sure trick, he may show a new suit or raise the opener's suit. With 8 or 9 high-card points and a balanced hand, the responder bids 3NT.

Responses to Preemptive Bids. Since the opener has overbid his hand by two or three tricks, the responder's high cards are the key factors to be considered when contemplating a raise. One or two trumps are sufficient support.

Responses to a One Notrump Bid. Balanced hands. Raise to 2NT with 8 or 9 points, or with 7 points and a good five-card suit. Raise to 3NT with 10 to 14 points. Raise to 4NT with 15 or 16 points. Raise to 6NT with 17 or 18 points. Raise to 7NT with 21 points.

Unbalanced hands. With fewer than 8 points plus any five-card suit, bid 2, 2, or 2. (Do not bid 2 on a five-card club suit.) With 8 points or more and a 4-card major suit, bid 2. (This is an artificial bid, asking the opener to show a four-card major if he has one. See section on rebids by opening 1NT bidder.) With 10 points and a good suit, bid three of that suit. With a Six-card major suit and less than 10 points in high cards, jump to game in the suit.

Responses to a Two Notrump Opening. Balanced hands. Raise to 3NT with 4 to 8 points. Raise to 4NT with 9 to 10 points. Raise to 6NT with 11 or 12 points. Raise to 7NT with 15 points.

Unbalanced hands. With a five-card major suit headed by an honor, or any six-card major, plus 4 points, bid the suit at the three-level.

Responses to a Three Notrump Opening. Show any five-card suit if the hand contains 5 points in high cards. Raise to 4NT with 7 points. Raise to 6NT with 8 or 9 points. Raise to 7NT with 12 points.

Rebids
Rebids by Opening Bidder. The opener's rebid is frequently the most important call of the auction. The opener now has the opportunity to reveal the exact strength of the opening bid and, therefore, whether a game or slam is contemplated. The opening is valued according to the following table:

13 to 16 points - Minimum hand
16 to 19 points - Good hand
19 to 21 points - Very good hand

After partner has raised the opening bidder's suit: Add 1 point for the fifth card in trump suit; add 2 additional points for the sixth and each subsequent trump. No four card is rebiddable; a five card suit is rebiddable if it is Q-J-9-x-x or better; any six card suit is rebiddable if it is x-x-x-x-x-x.

13 to 16 points. If partner has made a limited response (1NT or a single raise) the opener should pass, as game is impossible. If partner bids a new suit at the one-level, the opener may make a single raise with good trump support, rebid 1NT with a balanced hand, or, with an unbalanced hand, rebid the original suit or a new suit (if he rebid does not go past the level of two in the original suit).

16 to 19 points. If partner has made a limited response (1NT or a single raise) the opener should bid again, as game is possible if responder has maximum values. If the responder has bid a new suit, opener may make a jump raise with four trumps, or jump in his own suit if he has a six-card suit, or bid a new suit.

19 to 21 points. If partner has made a limited response (1NT or a single raise) opener may jump to game in either denomination, according to card strength and distribution. If the responder has bid a new suit, the opener may make a jump raise to game with four trumps, or jump to game in the original suit if it is strong. With a balanced hand and 19 or 20 points, the opener should jump to 2NT. With 21 points, rebidder should jump to 3NT. With 22 points and up, he should jump in a new suit (forcing to game and suggesting a slam).

Rebids by Opening Notrump Bidder. The Stayman Convention, populized by Bridge great Samuel Stayman, is an artificial set of bids that is very popular in both tournament and social play. When the responder bids 2, the opening bidder must show a four-card biddable major suit if he has such a suit:

With four spades, the player bids 2;
With four hearts, the player bids 2;
With four cards in each major, the player bids 2;
With no 4-card major suit, the player bids 2.

The opening Notrump bidder must pass: When the responder raises to Two Notrump and the opener has a minimum (16 points); when responder bids 2, 2, or 2, and the opener has only 16 or 17 points and no good fit for the responder's suit; when the responder bids 3 Notrump, 4, or 4.

Defensive Bidding
Overcalls. An overcall is a defensive bid (made after the other side has opened the bidding). Prospects for reaching game are not as good as they are for the opening bidder, in view of the opponent's bid strength. Therefore, safety becomes a prime consideration; overcalls are based not on a specified number of points, but rather on a good suit. Generally speaking, the overcaller should employ the same standards as a preemptor, with the ability to win in his own hand within two tricks of the overcall bid if vulnerable and within three tricks if not vulnerable.

One Notrump Overcall. An overcall of 1NT is similar to a 1NT opening bid and shows 16 to 18 points with a balanced hand and the opening bidder's suit well stopped.

Jump Overcall. Any jump overcall, whether it is a single, double, or triple jump, is preemptive and shows a hand weak in high cards but with a good suit that will produce within three tricks of the bid if not vulnerable and within two tricks if vulnerable.

Takeout Doubles. When a defender doubles and all the following conditions are present: a) his partner has made no bid, b) the double was made at the doubler's first opportunity, c) the double is of one, two, or three of a suit-it is intended for a takeout and asks partner to bid his best (longest) suit. This defensive bid is employed on either of two types of hand: 1) a hand of opening-bid strength where the doubler has no strong or long suit of his own but has good support for any of the unbid suits, or 2) where the doubler has a good suit and so much high-card strength that he fears a mere overcall might be passed out and a possible game missed.

Overcall in Opponent's Suit (cue-bid). The immediate cue-bid (for example: opponent opens 1; defender bids 2) is the strongest of all defensive bids. It is unconditionally forcing to game and shows approximately the equivalent of an opening forcing bid. It normally announces first-round control of the opening bid suit and is usually based on very fine support in all unbid suits.

Action by Partner of Overcaller. An overcaller's bid is based on a good suit; therefore, less-than-normal trump support is required to raise (Q-x or x-x-x). A raise should be preferred by the partner to bidding a suit of his own, particularly if the over-caller has bid a major. The partner of the overcaller should not bid for the sole purpose of keeping the bidding open. A single raise of a 1NT response should be made only in an effort to reach game. If appropriate values are held, a jump to game is in order, since a jump raise is not forcing.

Action by Partner of Takeout Doubler. In this situation, the weaker the hand, the more important it is to bid. The only holding that would justify a pass would be one that contained four defensive tricks, three in the trump suit. The response should be made in the longest suit, though preference is normally given to a major over a minor.

The doubler's partner should value his hand as follows: 6 points for a fair hand; 9 points for a good hand; 11 points for a probable game. A doubler's partner should indicate a probable game by jumping in his best suit, even if it is only four cards in length.

Since the partner of a doubler may be responding on nothing, it is a good policy for the doubler to subsequently underbid. while the doubler's partner should overbid.

Action by Partner of the Opening Bidder (when the opening bid has been overcalled or doubled). When an opener's bid has been overcalled, the responder is no longer under obligation to keep the bidding open; so a bid of 1NT or a raise should be based on a hand of at least average strength. Over a takeout double, the responder has only one way to show a good hand - a redouble. This bid does not promise support for the opener's suit but merely announces 10 points or more. Any other bid, while not indicative of weakness, shows only mediocre high-card strength.

Slam Bidding
When a partnership has been able to determine that they have the assets for a slam (33 points between the combined hands plus an adequate trump suit), they need only make sure that the opponents are unable to take two quick tricks. Various control-asking and control-showing bids have been employed through the years, but only three have stood the test of time: Blackwood, Gerber, and cue-bids (individual ace-showing). Blackwood is the most popular convention in Bridge. It was invented by Easley Blackwood in 1934.

Blackwood Convention. After a trump suit has been agreed upon, an immediate bid of 4NT asks partner to show his total number of aces.

Responses:
5 - no aces or all four aces
5 - one ace
5 - two aces
5 - three aces

After aces have been shown the 4NT bidder may ask for kings by now bidding 5NT.

Responses:
6 - no kings
6 - one king
6 - two kings
6 - three kings
6NT- four kings

Gerber Convention. Invented by John Gerber, this convention is similar to Blackwood in that it asks for the number of aces. It is used when the partnership has agreed that the final contract will be played in Notrump.
Its advantage is the fact that it initiates the response at a lower level. A sudden bid of 4 where it could not possibly have a natural meaning (Example: opener, 1NT; responder, 4) is Gerber and asks partner to indicate the number of his aces.

4 – no aces or all four aces

4 – one ace

4 – two aces

If the asking hand desires information about kings, he bids the next higher suit over his partner's last response. Thus, if the responding hand has bid 4 over 4 to indicate one ace, a bid of 4 would now ask for kings, and the responder would now reply 4NT to signify no king, 5 to signify one king and so on.

Cue-bidding (Individual Ace-Showing). The Blackwood and Gerber conventions are designed to cover only a small number of potential slam hands. Many slams depend on the possession of a specific ace, rather than a wholesale number of aces. Cue-bids are employed in such cases.
For example: Opener bids 2 and the responder bids 3 the opener now bids 4 this bid indicates the ace of clubs and invites the responder to signify an ace if he has one. The responder "signs off" by bidding the agreed trump suit.