In this article the phenomenology, psychodynamics, classification, etiology and the course of adolescent borderline and schizotypical pathology are reviewed on the basis of relevant literature. Much of what we know of the borderline pathology in adults seems to be useful to our understanding of adolescents. There are no empirical data about the predictive validity of the diagnoses schizotypical and borderline disturbance of the adolescent and _ if it is investigated _ this validity will possibly be small. In further investigation we shall have to take into account other kinds of psychopathology in this group of patients more emphatically than has been usual hitherto. Then, a finding may be that other psychopathology will influence the prognosis more than the borderline and schizotypal disturbances discussed here.