Advances in Clinical Child Psychology is an annual series designed to bring summaries of the latest developments in the field to psychologists, psy chiatrists, educators, and other professionals who are concerned with troubled children. This volume, like its predecessors, attempts to high light the important emerging issues and breakthroughs that are likely to guide clinical work and research in our field of inquiry in the near future. In selecting authors to contribute to this series, we seek out those whose work is innovative, relevant, and likely to influence future work in clinical child psychology and related fields. Each author is chosen either on the basis of potentially important new information or view points in his or her own work, or because the author is especially well qualified to discuss a topic that is not restricted to one program of research. In this volume, a wide range of particularly important topics is addressed. White and Sprague describe an innovative program of re search aimed at identifying the underlying deficit in attention-deficit disorder. Schonert-Reichl and Offer summarize and integrate research on gender differences in psychological symptoms among adolescents. Borden and Ollendick offer a cogent proposal concerning the develop. ment and differentiation of subtypes of autism based on social behavior."