Launched in 1971, <EM>Adolescent Psychiatry</EM>, in the words of founding coeditors Sherman C. Feinstein, Peter L. Giovacchinni, and Arthur A. Miller, promised "to explore adolescence as a process . . . to enter challenging and exciting areas that may have profound effects on our basic concepts." Further, they promised "a series that will provide a forum for the expression of ideas and problems that plague and excite so many of us working in this enigmatic but fascinating field." For over two decades, <EM>Adolescent Psychiatry</EM> has fulfilled this promise. The repository of a wealth of original studies by preeminent clinicians, developmental researchers, and social scientists specializing in this stage of life, the series has become an essential resource for all mental health practitioners working with youth. <BR><BR>Volume 23 of <EM>The Annals</EM> begins with the late Richard Marohn's reexamination of Peter Blos's concept of "prolonged adolescence," followed by contributions on the developmental roots of adolescent disturbances, the role of family interactions in adolescent depression, the establishment of a therapeutic alliance with adolescents, and the treatment of narcissistically disordered adolescents. The assessment and treatment of adolescent substance abuse and of psychosomatic and depressive symptoms in adolescence receive timely consideration. In a concluding section on "School-Based and Preventive Programs," contributors address a range of important issues, from adolescent sex and AIDS, to the provision of mental health services in public and private schools, to the need for school-based suicide postvention programs. In summary, volume 23 shows adolescent psychiatry to be as vital as ever, building on the clinical wisdom of the past while responding to the urgent challenges of the day.