In this article, the authors examine teacher identity development to understand more completely the intellectual and pedagogical demands of the profession. Drawing on interviews, observations, and reflections of two alternatively certified mathematics teachers, and contextualizing these data with surveys from 157 teachers in the same certification program cohort, the authors examine how identities evolved over the course of the teachers’ first year of teaching. These identities are explored in relation to the teachers’ knowledge of mathematics, their mathematics teaching, and their relationships to urban youth.