This article reviews the relation between evidence-based medicine and epidemiology and the recent evolution of the former. The meaning of evidence and the international efforts to collect, summarize, and disseminate findings from scientific research that are relevant for medical decision making are discussed. Evidence, current resources, and people's values, all play a role in making evidence-based medical decisions. This also has important implications for public health practice. However, decision making differs considerably between clinical care of individual patients and public health decision and policies that normally apply to populations. Although more closely related to epidemiology than clinical medicine, public health should also adopt a more systematic approach to evidence-based practice.