During the summer of 1982, 218 randomly-selected migrant farmworkers in Wayne County, New York were interviewed to determine the significant factors affecting use of health services among migrant farmworkers. Three groups were identified: immigrants, recent migrants, and long-term migrants. Medical utilization patterns, use of community medical services, types of health problems for which medical treatment had been delayed, reasons for the delay, and the migrant's subjective assessment of quality of community health care were compared among the three groups. A multiple regression model examined determinants of physician visits. The 113-item survey instrument covered individual and family characteristics, health habits and attitudes, health status, utilization of health services, home community characteristics, and the current resident's physical environment. Findings included that immigrants visited physicians less often; female migrants visited doctors more often; medical treatment was usually delayed due to fear of medical practices and disbelief in the medical profession; and lack of time and lack of access were reasons often cited for not seeking health care. Results indicated that the provision of comprehensive health programs, removal of structural barriers in the health delivery system, and a program of migrant health education are necessary to alter the medical utilization behavior of migrant farmworkers. (NQA)