The aim of this paper is to give an account of the response of secondary schools to the primary school foreign language teaching initiative recently introduced by the UK government. The paper also explores defining features of the process of cross-phase interaction and the role that knowledge and collaborative practice plays in generating change in perceptions and pedagogical practice. Our analysis draws on evidence from survey and case study interview data collected in a longitudinal study of the impact of the language policy initiatives on secondary school foreign language provision. (Contains 3 tables and 1 figure.)