Portfolios are increasingly being used to stimulate teachers' reflections. Frameworks for reflection on teaching often emphasize competencies and behaviours. However, other aspects of teacher functioning are also important, such as the teaching environment and individual teachers' beliefs, professional identity and mission. In a study among five medical school teachers, we explored how a portfolio stimulated reflections on the various aspects of teaching functioning. Outcomes of written portfolio assignments were collected and analysed to identify examples of reflections on the various aspects of teacher functioning. Examples of reflections on all aspects of teacher functioning were found, although examples of reflections on competencies were easier to find than those on beliefs, identity and mission. This study might help teachers and their trainers and coaches to recognize different aspects of teacher functioning when discussing portfolios for professional development purposes. However, further development of assignments and other methods to stimulate reflections on beliefs, identity and mission are needed. Furthermore, apart from the content of teachers’ reflections, teachers’ reflection processes should be researched, as well as the effects of portfolio meetings with peers and coaches.