Psychotherapist Greenberg combines expert knowledge with unimposing reassurance, respect for his young readers, and the experienced practitioner's sensitivity to just what kids might be uneasy or in the dark about. (Atone point he expresses surprise at what adults assume kids already know.) He covers the usual topics--how to tell if you need help, specific problems common with adolescents (depersonalization, depression, juvenile delinquency, running away, sexual hangups), types of therapy, stages in treatment, choosing a therapist--with just as much easy readability but no mush, far more authority and substance than is mustered in the usual guide for teenagers, and without the uncomfortable hedging of some. And when Greenberg brings in an example, often from his own practice, it bas an authentic ring, unlike all those obvious composite contrivances in journalists' guides. On the bugaboos of drugs and sex he recognizes possible problems but recognizes also that more kids are sent for treatment simply because their parents can't accept their normal behavior; and his assessment of different approaches to therapy (""talk,"" group, behavior, even running and meditation) is equally tolerant and sensible. The tone is right, the guidance sound, the information relevant.