Minority attack

In chess, a minority attack is the advancement of one's pawns on the side of the board where one has fewer pawns than their opponent, intending to use their minority to strategically provoke a weakness (i.e, an isolated or backward pawn) in the opponent's pawn structure. The minority attack is a common middlegame plan that can be played in many pawn structures. The name might be misleading, as the "attack" does not involve tactics planned to produce checkmate or significant material gain, but rather a strategical and structural advantage for the attacking player.

The minority attack can be strengthened by the moving of one or both rooks to the files where the attacking player intends to advance their pawns, planning prophylactically for the opening of the files. Common openings that result in pawn structures where a minority attack is effective include the Queen's Gambit Declined and the Caro-Kann Defense. The minority attack occurs most commonly on the queenside, as players commonly castle kingside in openings where a minority attack is effective, and the advancement of the pawns on the side of the castled king is widely considered to severely weaken the king's safety.

Karpov vs Lautier, 1995
This game, lauded as an example of a successful minority attack, demonstrates the goals and execution of the attack. In the diagrammed position, Anatoly Karpov has just played '''20. b4!''' initiating the minority attack. After '''20... Ng6 21. a4 a6 22. Bc3 Qg5 23. Bd4 Bxd4 24. Nxd4 Bd5 25. e4 Be6 26. Nf3 Qf4 Karpov plays 27. b5!''', provoking a weakness and threatening to severely impede Joël Lautier's pawn structure by capturing on a6 or c6, creating an isolated pawn and leaving Lautier three pawn islands. After '''27... axb5 28. axb5''' the game lasted 44 moves before Lautier resigned due to Karpov's passed d-pawn and the weakness of his own c-pawn.

Petrosian vs Krogius, 1959
In this position, World Champion Tigran Petrosian has just played '''12. b4''', initiating the minority attack and intending to advance both the a and b-pawns to provoke weaknesses in black's queenside majority. After '''12... Bf5 13. Bxf5 Nxf5, Petrosian played 14. b5!''' On move 22, the advancement of white's queenside pawns resulted in a destruction of black's queenside pawn structure and the creation of two isolated pawns for black, creating a decisive advantage for Petrosian.

Seirawan vs Tal, 1983
In this position, Syrian-American Grandmaster Yasser Seirawan has just played '''13. b4''' against the former World Champion Mikhail Tal, expanding his a and b-pawn minority on the queenside against Tal's a, b, and c-pawn majority. Tal responded 13... a5!?, counterattacking Seirawan's queenside and hoping to isolate the b-pawn. The game continued '''14. Be2 axb4 15. axb4 Rxa1+ 16. Qxa1 Qe7 17. Qc3 Nc6 when Seirawan continued 18. b5!''' removing the knight from the powerful c6 square and advancing his b-pawn. The game further continued '''18... Nd8 19. O-O c5 20. bxc6 bxc6 21. Rd1,''' and black's weak c-pawn fell on move 33, creating a decisive structural advantage for Seirawan.