Opposition (chess)

In chess, opposition (or direct opposition) is a situation in which two kings are two squares apart on the same rank or file. Since kings cannot move adjacent to each other, each king prevents the other's advance, creating a mutual blockade. In this situation, the player not having to move is said to have the opposition.^[1] It is a special type of zugzwang and most often occurs in endgames with only kings and pawns.^[2] The side with the move may have to move their king away, potentially allowing the opposing king access to important squares. Taking the opposition is a means to an end, normally to force the opponent's king to move to a weaker position, and is not always the best thing to do.

There are extensions of direct opposition, such as diagonal opposition and distant opposition, which can be conducive to reaching direct opposition. All three types may be referred to simply as opposition if the type is unambiguous in context.