A prolonged period of depersonalization resolved in this 16-year-old boy with only supportive therapy. Reasons for the depersonalization and withholding of other treatment are discussed. Observations are shared of the very intriguing phenomenon of derealization and allied conditions, psychiatric syndromes which are appearing with increasing frequency among so-called "normal adolescents" who indulge in drugs or other experiences which alter the state of consciousness, and among adolescents who survive disasters or harrowing experiences.