The Exchange Variation of the Ruy Lopez is a chess opening that begins with the moves: Black may recapture on c6 with either pawn; although 4...bxc6 is playable, 4...dxc6 is almost always chosen at master level.

White aims to reach an endgame with a superior pawn structure, which may become an important factor.

Thus, Black is compelled to strive for an active position, generally avoiding piece exchanges.

The variation was introduced into grandmaster play by Emanuel Lasker, and later invigorated with new ideas by Bobby Fischer.

Lasker's famous win against Jose Raul Capablanca in the St. Petersburg 1914 chess tournament is an example of this.

With a lead in the tournament, Capablanca was intent on simplifying the game to obtain a draw, but faced with the Exchange Ruy Lopez he played too passively and was routed by Lasker as a result.

[4] White now threatens 6.Nxe5 because the sequence 6...Qd4 7.Nf3 Qxe4 to regain the pawn, now fails to 8.Re1 pinning and winning the queen.

The idea behind these moves is that if White plays to win a pawn with 6.Nxe5, 6...Qd4 7.Nf3 Qxe4 is again playable, as the Black minor piece on e6 or e7 blocks the e-file.

After Black defends the e5-pawn, White's main idea is to play d2–d4, opening lines and freeing pieces.

Multiple trades have occurred, however, bringing the position closer to an endgame, which is beneficial for White, who has the better pawn structure.

White can play 7.Qxd4 (Fischer chose the more obscure 7.Nxd4 in two Exchange Variation games in his 1992 match with Boris Spassky), offering a trade of queens that Black should take to avoid a worse position.

12.Qxf3, White is safe and has the superior pawn structure, which is considered to offer a small advantage in the ensuing queenless middlegame.

This line is a favorite of Oleg Romanishin, who employed it successfully on multiple occasions.

Black gains the half-open b-file, but the central pawn structure becomes awkward.

The queen bishop has a particularly hard time finding a square, since moving the d-pawn leaves the c6-pawn undefended.

If 5.Nxe5, Black regains the pawn with 5...Qg5 6.Nf3 Qxg2 7.Rg1 Qh3; White has lost the right to castle kingside but has a lead in development.