Key ideas
- The usual sequence is 4.Nc3 exd5 5.cxd5 d6, followed by ...g6, ...Bg7, ...O-O, ...Re8, ...a6 and ...b5. The long diagonal and the queenside majority give dynamic counterplay, while d6 is a permanent weakness.
- White's main set-ups are the Classical, with e4, Nf3 and Be2; the Four Pawns Attack, with e4 and f4 aiming at e5; the Taimanov Variation, with f4 and Bb5+; and the Fianchetto, with g3 and Bg2.
- The Taimanov Variation, 6.e4 g6 7.f4 Bg7 8.Bb5+, is a serious test. The check disrupts Black's development, and 8...Nfd7 is the usual reply.
- In the Classical lines White often reroutes the king's knight to c4 by way of d2, adding pressure on d6 and preparing e5. The Snake Variation, 5...Bd6, is an offbeat alternative for Black.
Plans for White
Restrain Black's queenside with a4, keep e4 protected, and prepare e5 to break through in the centre. A knight on c4 hitting d6 and a central pawn break before Black's ...b5 arrives are the core plans.
Plans for Black
Play actively at once: ...a6 and ...b5, ...Re8 against e4, and knights heading for e5, or for c7 by way of a6 to support ...b5. The g7 bishop is the heart of the position, and exchanging it usually leaves d6 and the dark squares weak.
Watch out
In the Taimanov Variation, 8.Bb5+ Nbd7 runs into 9.e5. The knight on f6 has no good square, and after 9...dxe5 10.fxe5 Nh5 11.e6 Black's position is torn open. That is why 8...Nfd7 is played.
For the wider picture, see the Benoni Defense guide.