The inclusion of health education in high quality primary care has been suggested on the basis of 1) definitions and descriptions and descriptions of the content of primary care practice; 2) observational studies which have found that about 25 per cent of the direct patient-care time of the primary care physician is devoted to health education and counseling; and 3) surveys of physicians, who identified the most important "critical incidents" contributing to desired medical outcomes. This article reviews empirical studies of the role of health education in improving behavioral and medical outcomes for such conditions as hypertension, diabetes, congestive heart disease, streptococcal infections and others. Other contributions of health education in primary care in schools and other community settings are cited. Finally, the possible role of health education in medical education programs is described.