Traditionally, developmental psychology has been characterized by two approaches, one predominantly social and the other, cognitive. Despite this separatism, develop-mentalists have expressed the need for a better understanding of how these two facets of the person interact - a need for a better account of development within the person as a whole. However, such an integration has been difficult given the incompatibility of underlying assumptions guiding these two areas of inquiry. James Mark Baldwin's integration of social and cognitive development into (...) one theory highlights the utility of historical analyses for further progress in the field. In this paper, Baldwin's dialectical theory of personal growth is placed in historical context, highlighting similarities and differences between his approach and that taken by Piaget, and the legacy of his theory in current theory and research. The importance of self, the development of knowledge in the context of social relationships and the function of imitation are emphasized. (shrink)