An increasingly complex and ambitious conception of assessment that aims to enhance learning has seen the move from formative assessment to assessment for learning (AfL). In this study, an interpretive, qualitative approach was used to compare 21 practising teachers’ understandings of AfL prior to and at the conclusion of an undergraduate course and to investigate the courserelated experiences identified by these teachers as having had an influence on their post-course understandings. Data were gathered both through the generation of artefacts during the course and through post-course individual interviews. Although teachers’ pre-course understandings were an outmoded interpretation of Afl, post-course understandings showed significant shifts in teachers’ knowledge and understandings. The combined use of conventional and experiential approaches to support teacher learning was identified as a key factor in course members’ rethinking of the roles and responsibilities of students and teachers within an AfL environment.