We use German SHARE data to study the relationship between district general practitioner density and the quality of preventive care provided to older adults. We measure physician quality of care as the degree of adherence to medical guidelines (for the management of risk factors for cardiovascular disease and the prevention of falls) as reported by patients. Contrary to theoretical expectations, we find only weak and insignificant effects of physician density on quality of care. Our results shed doubt on the notion that increasing physician supply will increase the quality of care provided in Germany's present health care system.