In cultural anthropology, reciprocity refers to the non-market exchange of goods or labour ranging from direct barter (immediate exchange) to forms of gift exchange where a return is eventually expected (delayed exchange) as in the exchange of birthday gifts. It is thus distinct from the true gift, where no return is expected.

When the exchange is immediate, as in barter, it does not create a social relationship. When the exchange is delayed, it creates both a relationship as well as an obligation for a return (i.e. debt). Hence, some forms of reciprocity can establish hierarchy if the debt is not repaid. The failure to make a return may end a relationship between equals. Reciprocal exchanges can also have a political effect through the creation of multiple obligations and the establishment of leadership, as in the gift exchanges (Moka) between Big Men in Melanesia. Some forms of reciprocity are thus closely related to redistribution, where goods and services are collected by a central figure for eventual distribution to followers.

Marshall Sahlins, an American cultural anthropologist, identified three main types of reciprocity (generalized, balanced and negative) in the book Stone Age Economics (1972). Reciprocity was also the general principal used by Claude Lévi-Strauss to explain the Elementary Structures of Kinship (1949), in one of the most influential works on kinship theory in the post-war period.