A relationship between people that involves a mutual exchange of donations of goods, services or favours. Inherent in reciprocal donation is the obligation to return a gift of culturally appropriate way. Failure to do so is likely to end the reciprocal relationship. Reciprocity requires adequacy of response but not necessarily math equality. Reciprocity is a common way of creating and continuing ties between people. See generalized reciprocity, reciprocity and negative reciprocity balanced.