Model mate

A model mate is an aesthetic classification of checkmate used in chess composition. The mate must be both pure and economical. It does not change the basic rule of checkmate; it describes how the pieces are coordinated in the final position.

In a pure mate, the mated king's square is attacked only once, and each vacant square around it is also attacked only once. An adjacent square occupied by a piece of the mated side counts as blocked and normally must not also be attacked by the mating side. A standard exception allows that overlap when the blocking piece has to remain pinned to its king for the mate to work.

In an economical mate, all pieces of the mating side participate in confining the king, although the king and pawns are traditionally allowed to be excluded from this requirement. When purity and economy are both present, the result is a model mate. This criterion can appear in moremovers, directmates of four or more White moves, in helpmates, where both sides cooperate to produce mate, and in other composition genres.