Exchange Variation

By capturing on d5 before committing the king's knight or the queen's bishop, White resolves the central tension at once. The cost is obvious: 4...exd5, chosen in roughly three games out of four, opens the diagonal of the c8-bishop and so removes the main strategic burden of the Queen's Gambit Declined. White accepts this in exchange for a fixed and well-charted pawn structure, the Carlsbad, whose long-term features are generally thought to favor the first player. Once a fairly uncommon choice, 4. cxd5 has become the principal continuation after 3...Nf6.

White holds a central pawn majority and Black a queenside one. White's two standard plans follow from this. The minority attack uses Rb1 and b2-b4-b5, then bxc6, to saddle Black with a backward c-pawn on the half-open file; recapturing with the b-pawn or a piece usually leaves Black worse off still. The alternative is central expansion with Nge2, f3 and e4. Black's trumps are the half-open e-file and the e4 square, which serves as a base for knights and for piece play against White's king. Black usually has to use this activity, since slow maneuvering tends to let White's structural plans take effect. Carlsen–Jakovenko, Nanjing 2009, and Evans–Opsahl, Dubrovnik 1950, are cited as model games for the central advance and the minority attack respectively.

The usual fifth move is 5. Bg5, the Positional Variation, which threatens 6. Bxf6 and 7. Nxd5 or the creation of doubled isolated pawns. The replies 5...c6 and 5...Be7 generally converge. A typical continuation is 5...c6 6. e3 Be7 7. Bd3 Nbd7 8. Qc2 O-O 9. Nge2 Re8 10. O-O Nf8 11. f3, preparing e4; with 9. Nf3 instead, White follows up with h3. After 5...c6, 6. Qc2 is the Reshevsky Variation, though it often transposes back, while 6. e3 Bf5 7. Qf3 Bg6 8. Bxf6 Qxf6 9. Qxf6 gxf6 leads to an endgame. The Carlsen Variation, 5...Be7 6. e3 h6 7. Bh4 Bg4, puts the freed bishop straight to work, whereas the Chameleon Variation sees White castle long, giving opposite-side castling.

The main alternative to 4...exd5 is 4...Nxd5, played in about a fifth of games, which most often transposes to the Semi-Tarrasch after 5. e4 Nxc3 6. bxc3 c5 7. Nf3. 4...Bb4 is rare. White can also reach a related structure through 1. d4 Nf6 2. c4 e6 3. Nf3 d5 4. Nc3 Nbd7 5. cxd5 exd5 6. Bf4, the Sämisch Variation. The engine regards the position as close to equal, and White scores moderately better in practice.