35 Develop a good project monitoring and evaluation plan based on project evaluation principles and best practices. Consider evaluating citizen science impact (e.g., on behaviour or policy) in collaboration with citizens and by involving them in the co-creation of evaluation key performance indicators (KPIs) and impact assessment instruments. This requires researchers to relinquish control over such processes and increasingly adopt co-evaluation principles such as participant ownership, openness, and reflexivity, (participant) transformation, flexibility, documentation and transparency, and time (slow research). Develop robust monitoring and evaluation plan 41 42 B CS P B CS P