Key ideas
- The main line, 7.Rc1 c6 8.Bd3, is a fight for a tempo. Black would like to take on c4 only after White's bishop has gone to d3, so that Bxc4 costs White a second bishop move. White delays Bd3 with useful moves, and Black waits with moves such as ...c6, ...h6 or ...a6 (7.Rc1 a6 is the Henneberger Variation).
- Capablanca's freeing manoeuvre runs 8...dxc4 9.Bxc4 Nd5 10.Bxe7 Qxe7 11.O-O Nxc3 12.Rxc3 e5. Two pairs of minor pieces come off and ...e5 opens the diagonal of the c8 bishop, which is Black's worst piece in the Queen's Gambit Declined.
- White's alternatives at move 7 include the Rubinstein Variation (7.Qc2), which adds pressure on the c-file and keeps long castling possible, and the Botvinnik Variation (7.Bd3). If White exchanges on d5 at some point, the Carlsbad structure appears and the minority attack becomes the main plan.
Plans for White
Put the rook on c1, delay Bd3 until Black has spent a move, and keep pieces on the board to make your extra space count. After Capablanca's exchanges, the bishop on c4 aimed at f7 and play on the d-file are White's main assets.
Plans for Black
Keep d5 firm, win the fight for the tempo with waiting moves, then release the position with ...dxc4 and ...Nd5. The c8 bishop measures your progress: once ...e5, or ...b6 with ...Bb7, brings it into play, most of Black's problems are solved.
For the wider picture, see the Queen's Gambit Declined guide.