Modern Defensive Bidding by Walt Sturm

Classical defensive bidding (light overcalls, off-shape Take-Out (T.O.) doubles to show opening strength) is both ineffective and suicidal. Light overcalls rarely achieve much except guiding the declarer to play better and, if you encounter a misfit, they expose you to a devastating penalty double. Off-shape T.O. doubles waste a round of bidding for the doubtful purpose of showing non-descript strength. This requires you to raise partner to assure support without showing any extra strength as well as exposing you to an intervening pre-empt.

The modern style of defensive bidding is simpler and more direct. Sound overcalls show a full opening bid. This allows partner to use most of your usual offensive system while providing more safety. T.O. doubles guarantee at least 3-card support for the 3 unbid suits, leaving partner well placed to compete as he sees fit. Any subsequent raise by doubler shows extras; support is assumed by his pass. An immediate jump by responder shows 9-11 points and is invitational; a cue bid shows 12+ and is game forcing unless doubler happens to be light.

Playing sound overcalls and disciplined T.O. doubles in direct position leads to having to make frequent trap passes. Balancer must protect partner in case he has been trapped. Generally, balancer sells out with length in opener`s suit. When short, he balances aggressively, doubling to protect trapped partner. Suit bids are weak and may be 4 cards.

(For more details, read Edgar Kaplan`s Defensive Bidding in Modern Bridge.)