Congruent evidence from several medical disciplines provides compelling argument fora preventive approach to atherosclerotic diseases. Intervention trials and community health education programmes are under way. Reasonable, safe and practical approaches are available for hygienic interventions within the medical system. But major impediments to medical and community researches and action in prevention include professional controversy and public confusion about risk factors and their management. It is suggested here that most of this controversy and confusion is unnecessary and much of it due to professional attitudes and experience. These attitudes appear to result from failure to distinguish adequately the risk, diagnosis and therapeutic decisions appropriate to a culture, in the population-at-large.