A position where pieces and/or pawns face off against each other without capturing. Such positions require precise calculation, and nerves of steel.

A position in which there are one or more exchanges possible, such as a pair of pawns facing each other on a diagonal where either can capture the other, is said to contain tension. Such a situation differs from a threat in that it does not need to be immediately resolved – for example, if both pawns are defended. The consequences of resolving the tension must be constantly considered by both players, in case there is a possibility of winning or losing material. This makes calculating the best move more complicated, and so there is a natural temptation to release the tension by making a like-for-like exchange (see simplification) or by moving the attacked piece. To keep the tension is to avoid resolving it, which is sometimes good advice depending on the position.