The Massachusetts program was designed to ease the crisis of correctional institutions by moving intervention of juvenile delinquents to a community based program of rehabilitation and reintegration. Evaluation of the program of rehabilitation shows that attitudes, values, and relationships of the juveniles undergo positive changes when they are isolated from the outside community, when group therapy and structured activity programs are used, and when personnel is carefully selected and establishes a good rapport with the juveniles. In contrast, the reintegration program is most successful when activities include the community at large under careful supervision of the treatment team; the treatment center is best located in the neighborhood of the juveniles under treatment. The findings suggest that treatment methods and locations for social reintegration and rehabilitation cannot overlap. Assessment of the effects of boarding school treatment on the psychological development of the juvenile delinquents at Boscoville and Boy's Farm indicate important changes in juveniles' personalities. Antisocial tendencies, social maladjustment, low self-esteem, and depressions are all reduced after treatment of 12 to 20 months. However, juveniles tend to regress after their release from the institution. While individuals with immature, 'fragile' personalities make the greatest strides during treatment, they regress most rapidly after release. Subjects who remain longest regress the most. On the whole, individuals with the strongest personalities at admission benefit most from treatment. The boys from Shawbridge's Boy's Farm regress less than do boys from Boscoville because Shawbridge provides postrelease support. The study findings demonstrate that treatment of juvenile delinquents in boarding schools has positive effects, and that changes in attitude are facilitated by temporary (12 to 18 months) isolation from the community. For greatest effectiveness in the long term, however, a postrelease program to encourage social reintegration must follow the rehabilitative treatment. Initial evaluation of the emotional development of juveniles to be treated must be undertaken to assure adaptation of the boarding-school and post-cure regime to the individual personality types. Notes are supplied.