Two typologies of family process, Olson's Circumplex Model and the Beavers Systems Model, are discussed, focusing particularly upon their definitions of family adaptability. It is argued that the two typologies are not simply “separate but equal” (11), but, rather, that there is an ambiguity in the Circumplex Model that disguises a fundamental theoretical overlap between the two. Olson's definition of adaptability is founded upon the concepts of morphogenesis and change; Beavers builds upon the concepts of negentropy and competence. It may be shown, however, that both understandings are necessitated by the theoretical writings of Olson and his colleagues. The nature of this ambiguity in the Circumplex Model is critically explored, and a higher-order model that attempts to synthesize these two theories is proposed.