The objective of this study was to obtain and critically evaluate data on the health characteristics and the need for medical assistance in patients aged 40 years and over, from six urban and rural medical practices in northern Israel, who have not consulted their family physician for at least 3 years. A health questionnaire was completed by means of telephone calls and personal contacts, regarding 139 non-visitors (out of 1847 patients aged 40 and over). The health characteristics and prevalence of medical and social problems were compared to regular clinic attenders. Questionnaires of 101 non-attenders were completed for a response rate of 73% (101/139). The non-attendance rate was 7.5% (139/1847) and there was a low rate of morbidity. The majority (81%) were 40-59 years old and only 16% had had previous illnesses. Only 10% took medications regularly, most of them medical personnel. Twenty-eight of the non-attenders were employees of the regional health care system. Most of these individuals coped with chronic illnesses by consulting the regional hospital's outpatient clinics. Non-attenders could be characterized as less prone to health problems. Most of them seemed remarkably fit and were not suffering unduly as a result of their lack of medical attention.