The advantage and desirability of early treatment in all forms of mental disorder are now generally accepted. The treatment of general paralysis of the insane by malaria, of schizophrenia by shock therapy and of the neuroses by psychotherapy covers a wide range of different methods, yet no one would hesitate to stress the importance of starting the treatment in each case as early as possible. Nor must the necessity of prophylaxis be forgotten, with the consequent importance of child guidance.