The concept of "clinical epidemiology" is well established in the New World; indeed most of the quotations and works cited in this paper come from the United States and Canada. On the other hand, the concept seems to remain controversial in most countries in the Old World. From an exploration of the interface between the approaches used by epidemiologists on the one hand, and clinicians (including psychiatrists) on the other, this paper discusses aspects of the relationship between "conventional" and "clinical" epidemiology; in particular questions are raised as to whether these are part of the same continuum or whether they are separated by a gulf. At present, answers to such questions depend on subjective positions as well as on objective criteria. In order to reach a consensus on these questions, further concertation especially among epidemiologists, will be needed.