It is necessary to establish the presence or absence of a borderline schizophrenic reaction early, for it is of great importance in deciding on the treatment program for the patient. Its presence is suspected if there are symptoms that indicate that the patient is developing a thought disorder, and/or a disturbance of affect of schizophrenic type, and/or is beginning to detach from reality. It is also suspected if there is a persistence of such symptoms as disturbances of judgment, poor empathy and understanding of others, an absence of enjoyment, periods of seclusiveness, or sexual and philosophical preoccupations. Mixtures of the neuroses, with free-floating anxiety often indicates an underlying schizophrenic process. In the treatment of a patient with a borderline schizophrenic reaction, the prime focus should be on the prevention of a psychosis. The child should be protected against severe stresses, which may involve some environmental manipulation. Anxiety has a deteriorating effect and tranquillizers may have to be used. Supportive psychotherapy is of great value. It is essential that the relationship with the therapist be a positive one. The therapist should be a real person who offers the adolescent patient someone with whom to identify. One strengthens useful defences and lessens the need for the other defences by reducing the ego's needs for those defences, e.g. by reality testing the fantasied threats, by offering a less punitive and less rigid superego, and by manipulating the environment to reduce stress. It is often helpful to orient the patient towards pleasurable experiences which have an ego-strengthening effect. Here then, in the handling of the defences and in the management of anxiety, can be seen a major difference in the treatment of patients with a borderline schizophrenic reaction, from the treatment of patients with psycho-neuroses or personality disorders. Failure to recognize the presence of an underlying schizophrenic process may lead to the choice of the wrong treatment program for the patient, with a resultant worsening of his condition and the onset of a psychosis.