Background: The Western classical training of many secondary music specialist teachers may be inappropriate for the demands of the contemporary secondary school classroom, leading to a conflict between their self-concepts as "musicians" and as "teachers". Aims: To undertake a short-term longitudinal comparison of the developing identities and the attitudes of a group of intending specialist secondary music teachers, during the transition into their first teaching post, with a group of music students from university and conservatory backgrounds. Sample: Twenty-nine trainee music teachers completed Phases 1 and 2 of the study during their final weeks of training and during the second term of their teaching career, and a comparison group of 29 final-year undergraduate music students did so in the first and last terms of their final year. Method: A specially devised composite Musical Careers Questionnaire gathered information in both phases about self-efficacy in music and in teaching, identification with professional groups in these two domains, and attitudes towards important skills for musicians and teachers. Results: A series of ANOVAs comparing the student groups' scores in each of the two phases revealed no significant main effects or interactions for either of the self-efficacy measures, a significant group effect for professional group identification, and some changes in the attitude measures. Conclusion: Although participants' views of their own general effectiveness as teachers and as musicians changed very little over the period of the study, their attitudes towards music teaching and perceptions of the skills required showed some changes.