Queen's Gambit Declined: free opening course

Key ideas

• Hold d5 with ...e6 and ...Nf6: the centre stays solid and White cannot win space for free.
• The light-squared bishop is Black's problem piece. Free it with ...b6 and ...Bb7, with ...dxc4 then ...e5, or put it on e6 or f5 after an exchange on d5.
• Ease the pressure by trading: ...h6 asks the g5 bishop a question, and ...Ne4 swaps a pair of minor pieces.
• Once development is finished, strike back with ...c5 (or ...e5) to open lines for your pieces.
• In the Exchange structure, meet White's minority attack (b4-b5) with ...Ne4, ...Nf8-g6 and pressure on the kingside, rather than waiting.
• Never grab pawns on d5 or c3 without checking pins: the Bg5-d8 pin and the ...Bb4 pin both decide many early tactics.

The 6 variations in the course

• Orthodox: Tartakower Defence (...h6, ...b6): 1. d4 d5 2. c4 e6 3. Nc3 Nf6 4. Bg5 Be7 5. e3 O-O 6. Nf3 h6 … — Black castles, kicks the bishop with ...h6 and fianchettoes with ...b6 and ...Bb7. After White takes on f6 and plays b4, Black accepts hanging pawns on c5 and d5 that give active piece play.
• Lasker Defence (...h6, ...Ne4): 1. d4 d5 2. c4 e6 3. Nc3 Nf6 4. Bg5 Be7 5. e3 O-O 6. Nf3 h6 … — Black uses ...h6 and ...Ne4 to swap two pairs of minor pieces. With fewer pieces on the board Black's space problem disappears, and ...b6, ...Bb7 and ...c5 complete development.
• Exchange Variation (Carlsbad structure): 1. d4 d5 2. c4 e6 3. Nc3 Nf6 4. cxd5 exd5 5. Bg5 Be7 6. e3 c6 … — White exchanges on d5 early to fix the structure and plans the minority attack with b4-b5. Black builds a solid set-up with ...c6, ...Nbd7-f8 and uses ...Ne4 to trade pieces and gain kingside play.
• Ragozin Defence (...Bb4): 1. d4 d5 2. c4 e6 3. Nc3 Nf6 4. Nf3 Bb4 5. Bg5 h6 6. Bxf6 Qxf6 … — After 3.Nc3 Nf6 4.Nf3 Black plays ...Bb4, pinning the c3 knight. In the 5.Bg5 h6 6.Bxf6 Qxf6 line Black gets the bishop pair and quick counterplay with ...dxc4 and ...c5.
• Against the Catalan (Open, ...dxc4): 1. d4 Nf6 2. c4 e6 3. g3 d5 4. Bg2 dxc4 5. Nf3 Be7 6. O-O O-O … — Against White's g3 and Bg2 set-up, Black takes on c4 and defends the extra pawn just long enough to gain time with ...a6 and ...b5. The b7 bishop then challenges White's g2 bishop on the long diagonal.
• Cambridge Springs Defence (...c6, ...Nbd7, ...Qa5): 1. d4 d5 2. c4 e6 3. Nc3 Nf6 4. Bg5 Nbd7 5. e3 c6 6. Nf3 Qa5 … — Black uses the pin on the c3 knight: ...Qa5 and ...Bb4 hit c3 and the g5 bishop on the fifth rank. White usually plays Nd2 and Qc2, and Black breaks with ...e5 for active play.

Traps you will learn (2)

• Cambridge Springs: don't grab on c3 — A watch-out trap for Black. In the main Cambridge Springs line, after ...e5 and ...exd4, White's Nb3 attacks the a5 queen. Taking on c3 with the pawn looks like it wins a piece back with interest, but Black only gets two minor pieces for the queen.
• Cambridge Springs: g5 bishop falls — In the Cambridge Springs the a5 queen eyes g5 along the fifth rank. If White develops carelessly, ...Ne4 and ...dxc4 clear the rank and the g5 bishop or knight is lost.

How the opening courses work

Each course teaches an opening in a few main variations. For every move you read why it is played, which other moves are good, and which tempting moves are mistakes and why. Each course also shows the traps of the opening: the ones you can set and the ones to avoid.

After a lesson you play the moves yourself in a drill. The lines you learn go into your review, which brings them back when you are about to forget them (spaced repetition). 30 line courses add many short lines per opening, a few new ones a day, and every named opening, more than 3,800 lines, has a lesson of its own.