Key ideas
- The bishop on b7 supports ...c5 and watches the long diagonal. The inserted ...h6 gives the king air and makes the pin harder to maintain, since ...g5 or ...Ne4 can question the bishop on h4. White can avoid the system with 6.Bxf6, the Anti-Tartakower Variation.
- The most direct test is the exchange on d5. After 8.cxd5 Nxd5 9.Bxe7 Qxe7 10.Nxd5 exd5 11.Rc1 Be6, Black puts the bishop on e6 to guard d5 and prepares ...c5. This is the line of Fischer's win against Spassky in game 6 of their 1972 match, which continued 12.Qa4 c5 13.Qa3 Rc8 14.Bb5.
- After ...c5 and an exchange on c5, Black is left with hanging pawns on c5 and d5. Whether they are strong, controlling key central squares and ready to advance, or weak targets for White's pieces, is the central question of the variation.
- 8.cxd5 exd5 keeps more pieces on. The b7 bishop then looks at its own pawn on d5, and White develops with Bd3 and castles, with ideas such as Ne5 or a b4 push.
Plans for White
Exchange on d5, trade the dark-squared bishops, and play against d5 or the hanging pawns with Qa4, Rc1, Bb5 and rooks on the c- and d-files. Try to force one of the pawns forward, then blockade the other on c4 or d4.
Plans for Black
Get ...c5 in. With the bishop on b7 or e6 and rooks on c8 and d8, hanging pawns on c5 and d5 control important squares and can advance with ...d4 or ...c4 at the right moment. Avoid letting White's pieces settle on the blockading squares in front of them.
For the wider picture, see the Queen's Gambit Declined guide.