It is widely argued that nurse learners should learn to become reflective practitioners and that self-assessment plays a part in this (Ekebergh et al 2004, Thorpe 2004). Problems arise, however, when consideration is given to just how this might be achieved. This article examines the challenges of assessing reflection where self-assessment has played a part. It highlights the challenges that can arise when reflection and self-assessment are used for different educational purposes. It identifies why this work is challenging and suggests some parameters that may assist colleagues in making learning more successful.