Michael J. Chandler is Distinguished CIHR/MSFHR Professor in Developmental Psychology at the University of British Columbia in Vancouver, Canada. His research centers on the study of young people’s social-cognitive development, especially as such age-related changes bear on matters of interest to developmental psychopathologists and health professionals. Most recently his work has come to focus on cross-cultural comparisons of epistemic and identity development as these differently unfold in Canada’s Aboriginal and culturally mainstream youth. Christopher E. Lalonde is an assistant professor in the Department of Psychology at the University of Victoria. His research interests include social-cognitive development in childhood and adolescence and the influence of culture on identity development and determinants of health. Bryan W. Sokol is an assistant professor in the Department of Psychology at Simon Fraser University. In addition to his interests in identity development, Bryan’s research includes the study of children’s developing epistemic and moral reasoning. Darcy Hallett is a Ph.D. candidate in Developmental Psychology at the University of British Columbia. In addition to the subject matter of this Monograph and to identity development in general, Darcy’s research interests include epistemological development and children’s understanding of mathematics.