This Bernsteinian analysis conceptualizes No Child Left Behind legislation in the United States as a recent and deliberate shift towards a ''performance'' model of official pedagogic discourse. The paper posits that this shift carries the capacity to fundamentally alter teachers' professional practices and identities. It examines particularly whether the policy shift has impacted the professional practices and identities of pre-service and early career teachers, whose training has been completed in the wake of No Child Left Behind, differently than it has impacted the professional practices and identities of their veteran counterparts. (Contains 3 tables.)