Business alliances, by filling critical resource gaps, enable firms to have positional advantages that lead to superior financial performance. Some alliances, however, are more successful than others. The three prominent theoretical approaches to explaining alliance success rely on resources, competences, and relational factors. The authors theorize that the three approaches are interdependent and, using resource-advantage (R-A) theory as a framework, develop an integrative model. This model proposes that the three approaches are linked by means of relationships among (1) alliance competence, (2) complementary resources, (3) idiosyncratic resources, and (4) cooperation. A test of the model, using a sample of alliance professionals, finds support for the theory that the three approaches are, indeed, interdependent and that resources, construed in the manner of R-A theory, influence alliance success through positional advantage. © 2008 Elsevier Inc. All rights reserved.