This volume, a report of a National Institute of Mental Health Conference, presents a synopsis of the informal presentations and discussions along with a summary narrative and quotations from each of the three sessions. The first section of the book deals with adolescent personality, socioemotional, biological, and cognitive development. The second section focuses on the relationship of the adolescent with his/her family, peers, and school. The third section provides a roundtable discussion devoted to current research and conceptualization on stress responsivity. The report closes with a review of two longitudinal research programs dealing with ego resilience in children and adolescents. A references section and list of conference participants are appended. (JAC)