Triangulation

Triangulation is a maneuver, usually by a king, that spends one extra move without surrendering the position. The king travels through three squares and returns to its starting point while the opponent can only shuffle between two. When the basic position reappears, it is the other side's turn.

That change of turn may create zugzwang, a position in which every useful move worsens the result. A tempo is one move or turn in chess. A player who triangulates is therefore said to lose a tempo: the route takes three moves rather than two, but the delay serves a precise purpose.

The maneuver works only if all three squares are safe, the opponent has no waiting move, and the important structure remains unchanged. It may help a king reach the right corresponding square, force the opposing king aside, or prepare outflanking.