For decades, debates over medical curriculum reform have centred on the role of science in medical education, but the meaning of "science" in this domain is vague and the persistence of the debate has not been explained. Following Bourdieu, this paper examines struggles over legitimate knowledge and the forms of capital associated with science in contemporary UK medical education. Data are presented from a study of two UK medical schools, one with a traditional, science-oriented curriculum, another with an integrated curriculum. Constructions of legitimate knowledge were explored at both schools through six months participant observation, interviews with faculty members (n = 15) and students (n = 37) and documentary analysis. Findings show that medical schools compete for both scientific and clinical capital, but ultimately science has greater legitimacy. "Science" is defined in accordance with the structure of the traditional curriculum and has become a symbolic resource--a mark of distinction for both medical schools and medical students--which is equated with clinical competence. The significance of science is circumscribed by the medical education field, yet the struggles for scientific capital there have ramifications beyond medical education itself. It is argued that Bourdieu's concepts are particularly useful tools for studying the meanings that science takes on outside of the scientific field.