This paper argues that disease etiology is the key to cross‐cultural comparison of non‐Western medical systems. Two principal etiologies are identified: personalistic and naturalistic. Correlated with personalistic etiologies are the belief that all misfortune, disease included, is explained in the same way; illness, religion, and magic are inseparable; the most powerful curers have supernatural and magical powers, and their primary role is diagnostic. Correlated with naturalistic etiologies are the belief that disease causality has nothing to do with other misfortunes; religion and magic are largely unrelated to illness; the principal curers lack supernatural or magical powers, and their primary role is therapeutic. [disease, religion, and magic; ethnomedicine, medical anthropology, non‐Western medical systems, shamans]