This article is based on research with a group of one-year Postgraduate Certificate in Education secondary trainee teachers during their initial teacher education and training in England. It considers tensions between trainees' prior experiences and conceptions of teaching and their training programme. In doing so, it seeks to examine how a trainee's dispositions as revealed through practice in various contexts are reflective of Bourdieu's "habitus". Associated with this, the paper also examines how particular forms of pre-existing cultural capital and manifestations of biographical identity also pre-dispose trainees to form affinities and disaffinities within particular fields. Lacanian concepts of the symbolic, imaginary and real are used to help explain how trainee teachers articulate resonance and dissonance during their field experiences, particularly in relation to ontological concerns of securing a professional stable sense of self.