Abstract
Substitution decisions have been examined from a variety of perspectives. The economics literature measures cross-price elasticity, operations research models optimal assortments, the psychology literature studies goals in conflict, and marketing research has examined substitution-in-use, brand switching, stockouts, and self-control. We integrate these perspectives into a common framework for understanding consumer substitution decisions; their specific drivers (availability of new alternatives, internal vs. external restrictions on choice); the moderating role of a consumer's commitment to an initially desired alternative; and the affective, motivational, cognitive, and behavioral outcomes of substitution. We use this framework to recommend new avenues for research.