Impermanence (Sanskrit: anitya; Pali anicca; Tibetan: mi rtag pa; Chinese: 無常, wúcháng; Japanese: mujō) is one of the essential doctrines of Buddhism. According to it, everything is constantly in flux. This is embodied in human life in the aging process and the cycle of birth and rebirth (samsara), and in any experience of loss; because things are impermanent, attachment to them is futile, and leads to suffering.

Anicca is intimately associated with the doctrine of anatta, according to which things have no fixed nature.

See also: three marks of existence