OBJECTIVE To investigate the utilization of in-home services by severely mentally and physically handicapped persons at home in order to clarify the vital factors associated with the services. METHODS Questionnaires were delivered to 174 severely mentally and physically handicapped persons who were registered with 8 institutions in Tokyo and Kanagawa prefecture through each institution. One hundred and thirteen respondents among them were the subjects of this study. As a conceptual model Andersen's model was adopted. RESULTS (1) The age of subjects varied from 2 to 50. There were no subjects between the age of 7 to 17. The mean functional handicap severity score (SCORE) was 5.8 +/- 8.4 standard deviation. Ninety seven percent of main caregivers were mothers, even among the aged. (2) Over 1/2 of the subjects reported having utilized institutional services. On the other hand the percentage for visiting nurse service (VNS) and home help services were 28.3% and 7.7% respectively. (3) Subject who used V.N.S. had significantly higher SCORES and higher luck of health of caregivers. Caregivers utilized V.N.S. as a substitute to reduce their burden in activities care at home. On the other hand, users of institutional services showed high scores in difficulties with daily help and perceived difficulties with medical treatments: it showed that they sought institutional care to reduce there careburden. (4) Total number of used by each client for in-home service was explained only by both difficulties of daily help and SCORE from multiple regression analysis. CONCLUSIONS Users of visiting nursing service expect highquality care based on current medical knowledge and also with the aim of caregiver's health. With the increasing age of caregivers it appears to be important to enhance visiting nurse services, reduce the caregiver burden, and provide active support of home care for the handicapped.