The lives of women and men, the relationships that they establish, and their work have changed dramatically in the past 50 years, but the dominant theories driving research in these areas have not. In this article, the authors argue that the facts underlying the assumptions of the classical theories of gender and multiple roles have changed so radically as to make the theories obsolete. Moreover, a large body of empirical data fails to support the predictions flowing from these theories. Yet the development of new theory for guiding research and clinical practice has not kept pace. The authors attempt to fill this theoretical gap by reviewing the research literature and articulating an expansionist theory of gender, work, and family that includes four empirically derived and empirically testable principles better matched to today's realities.