THE differential diagnosis of schizophrenia in a behaviorally disturbed adolescent is a unique and difficult problem, primarily because adolescence is normally an unsettled period during which changing sexual and social demands antiquate previously adaptive response patterns, and successful solutions to the complexities of adult living hover mysteriously beyond the pale. As sensitively depicted by Sullivan (1953, pp. 263-310) and Erikson (1956, pp. 77-102), the adolescent must wrestle simultaneously with his relationship to himself, his parents, and his peers; with his needs to feel secure but also to endanger his security by risking intimate engagement in friendships and heterosexual associations; with responsibilities for demonstrating his capacity for independence and for deciding on his life goals; and with the perplexing task of identifying to himself exactly what kind of person he is-his sex, his interests, his capacities, arid his worth.