Challenges include missing or inconsistent data, differing interpretations of terms such as ‘additional activities’, lack of clear causality between actions and impacts, and difficulties in demonstrating contributions to policy goals. Partnerships should invest resources early to build capacity for data collection and evaluation. The European Commission is working to clarify terms and simplify evidence collection, and ERA‑LEARN did organise training sessions on monitoring and evaluation that partnerships should take advantage of. When developing partnership specific impact pathways, partnerships should ensure alignment with standard evaluation terminology and limit the number of indicators to those that are meaningful, measurable and manageable.