Queen's Indian Defense

The Queen's Indian Defense (QID, or Queen's Indian Defense in British spelling) arises after 3...b6, once White has chosen 3. Nf3 rather than 3. Nc3 and so avoided the Nimzo-Indian pin 3...Bb4. Black prepares to develop the queen's bishop, usually on b7, where it bears down the long diagonal onto e4 and d5, or on a6, where it eyes the c4-pawn. In hypermodern style Black restrains e2-e4 with pieces rather than occupying the center with pawns, and the opening is commonly paired with the Nimzo-Indian, its sister defense, as a repertoire against 1. d4.

The most frequent reply is 4. g3, the Fianchetto Variation, which challenges Black's bishop on the long diagonal. Through the 1970s the standard answer was 4...Bb7, and the classical line 5. Bg2 Be7 6. O-O O-O 7. Nc3 Ne4 8. Qc2 Nxc3 9. Qxc3 gives White extra space while Black stays free of weaknesses and finds counterplay with ...c5, ...f5 or ...Be4. Its tendency toward draws has made 4...Bb7 a common choice for Black when a draw is acceptable. From the 1980s the topical move has been 4...Ba6, attacking c4; after 4. g3 Ba6 5. b3 Bb4+ 6. Bd2 Black uses the check to draw White's bishop to an awkward square before striking with ...c6 and ...d5. A more recent try is 5. Qc2 Bb7 6. Bg2 c5 7. d5, a pawn sacrifice for activity taken up by grandmasters such as Veselin Topalov and Magnus Carlsen.

The Petrosian Variation, 4. a3, rules out ...Bb4 so that White can follow with Nc3 and e4 and build a broad center; Black typically fights for e4 with ...Bb7 and ...d5. Garry Kasparov used it often early in his career, and 4. Nc3 Bb7 5. a3 reaches the same setup by another order. After 4. Nc3 Black may also choose 4...Bb4, a hybrid with the Nimzo-Indian; in the database Black scores slightly better than White against 4. Nc3. The Spassky System, 4. e3, quietly prepares Bd3 and kingside castling and can pass into the Nimzo-Indian after 4...Bb7 5. Nc3 Bb4. The Miles Variation, 4. Bf4, has never attracted a wide following.

The resulting play is mostly positional, built on piece maneuvers around the e4 and d5 squares and timely pawn breaks such as ...c5 and ...d5 for Black or d4-d5 and e2-e4 for White. Results in the database are close to even, and the engine regards the starting position as roughly balanced. Former world champions Anatoly Karpov and Viswanathan Anand have used the defense regularly.