This discussion is a critical review of studies in ethnopharmacology, particularly as they contribute to some of the icy debates in anthropology. A central thesis is to illustrate through exposition and comparison the utility of a biobehavioral and multidisciplinary perspective. Thus, it is important to understand the cultural construction of efficacy and to appreciate the multiplicity of contexts in which plant use occurs. These considerations are applied in the exposition of several themes. (a) Understanding the origins and later refinements of plant utilization requires attention to what medicines mean and to the structural codes that guide their selection, preparation, and administration. Consideration of more strictly semiotic/mentalist interpretations, as well as of physiologic indicators, is appropriate. Investigations of plant domestication, including genetic and cultural manipulations of "secondary" metabolites, help to shed further light on these questions. (b) Understanding the different contexts in which plant use occurs-diet, medicine, manufacture , etc-helps us to assess the impact of botanicals on human health. (c) Ethnopharmacologic data have a still unexplored potential to help solve real health problems.