Abstract
This article tests a common fundamental assumption in Survival Value, Conflicting Loyalties, and Alliance Theory: that exogamy creates cross-alle giance/alliance between social units. The study finds little support for the theoretical statement on a worldwide, cross-cultural basis. Additional ex tensive investigation of sample societies reveals that high cross-allegiance / alliance appears moderately related to absence of primary cousin marriage. Suggestion is made for refinement of exogamic theory.