This paper draws on baseline data from the National Center for Research on Teacher Education to examine the approaches to learner diversity held by prospective teachers participating in five U.S. teacher education programs. Four layers of meaning given to the concept of diversity are proposed: individual, categorical, contextual, and pedagogical views of differences. In surveys and interviews with prospective teachers, it was found that individual and categorical views predominate, with psychological orientations and an emphasis on the individual underlying most of the responses. These beginners value ideals of equality and fairness but have difficulty envisioning concrete pedagogical means towards supporting these goals. Dilemmas that have shaped much of American educational history pose problems for these prospective teachers. These findings raise methodological and conceptual puzzles and hint at implications for teacher education practice. (Author)