King and queen checkmate

King and queen versus king can always force checkmate, even against the best defense. The queen can confine the enemy king to a steadily smaller area, but it needs help from its own king to finish the mate. An unsupported queen cannot safely occupy every square beside the enemy king.

A safe method

1. Use the queen to build a box around the enemy king and shrink that box without offering the queen.
2. Bring your king closer until it controls the squares near the confined area.
3. Force the enemy king to an edge and give the final check with a queen protected by your king.

The box closes without stalemate

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The queen prepares the boundary

The black king is on h7. The distance between the queen on g2 and the king on f5 allows the confinement to begin without exposing the queen.

The main technical danger is stalemate: a drawn position in which the player to move is not in check but has no legal move. It can occur if the queen removes every move before the attacking king is ready to deliver mate. The method resembles king and rook checkmate, although the queen confines the king more quickly.