Evaluation is a central feature of educational psychologists' (EPs) work. Different evaluation tools have been used in the published literature but a consistent approach is yet to emerge. Informed by Interpretative Phenomenological Analysis, this research asks what information EPs find meaningful when they evaluate their work. Six EPs working in a local authority educational psychology service were interviewed about their experiences of their work and how they knew they had made an impact. A diverse range of information drawn upon as evidence that there had been change was described. It is thus proposed that a tool which enables EPs to collate different types of information from a number of sources may be useful when evaluating their practice.