1. A study of 100 psychoneurotic women patients admitted to the New York Hospital, Westchester Division between 1927 and 1937 has been made.2. A review of the family background revealed that these individuals came pre-dominantly from large families in which mental illness was present frequently among the antecedents (in 68 cases).3. An analysis of the life histories revealed that the group as a whole enjoyed good physical health in infancy, but that they tended to be tense and insecure as indicated by the presence of neurotic traits in infancy in over one-half the cases. Half the patients were outgoing sociable and had many interests and these tended to do better under treatment than the other half who displayed narrowing of interests and shut-in personalities.4. The study of the present illness demonstrated that:(a) Psychoneuroses tend to be of long duration before hospital treatment is instituted.(b) Identification with close relatives suffering from serious physical or mental illness was an etiological factor in the illness of over half the patients.(c) Almost one half the group had been subject to surgical procedures shortly before hospitalization. The complaints leading to operation were in many instances apparently the result of visceral tensions and hypochondriasis rather than important physical pathology. These patients were resistive to treatment.5. The value of a full and varied program of activities supervised by the physician and fitted to the patients' needs and capacities, together with frequent psychotherapeutic interviews was substantiated by this study.6. The average length of hospitalization was nine months.7. Follow-up studies of 100 women with psychoneurotic disorders five to fifteen years after discharge revealed that 32 were recovered, 34 much improved, 17 improved making a total of 83 who had benefited by treatment (one of those discharged as much improved is not included as there has been a recurrence and she is now under treatment).8. Two case histories illustrating some of the above points were presented.