Pawn fixation

To fix a pawn is to prevent it from leaving its square safely. It may be stopped by another pawn, by a piece placed in front of it, or by control of the square to which it would like to advance. Once the pawn loses mobility, a weakness that might have disappeared through an advance or exchange becomes a more stable target.

Fixation is usually the first step rather than the complete plan. The attacker must then bring pieces against the pawn, restrict its defenders, or create a second threat. A friendly pawn may fix it by controlling its escape route, and a piece may blockade it. In either case, the technique forces the opponent to defend a feature that is difficult to repair.

The decision remains concrete. Fixing a pawn may close a line that friendly pieces needed or give the opponent a break elsewhere. A pawn ram is a structural form of mutual immobility, while a pawn hook can turn a fixed pawn into a point of contact for opening lines.