A major shortcoming of existing research on human migration is its lack of comparability. Widely different sets of explanatory variables, demographic groups, geographic units, and sample sizes have been used. Often the absence of explicit disciplinary theory makes it difficult to interpret these findings or make any confident generalizations or predictions about population shifts. In response to this weakness, this paper examines patterns of age-race specific net migration of males between United States metropolitan areas for I960 to 1970 using three models of migration, each of which has a distinct conceptual underpinning. The first model draws on several neoclassical economic perspectives, the second discusses the influence of non-traded goods, and the third derives and tests an ecological model of migration.