The recommendations presented in the current guidelines are built on a wealth of theoretical and empirical insights from several resources and 35 representatives from 19 European cities, and seven organisations, including academia and (non-)governmental organisations. As such, these guidelines reflect the collective understanding and experiences of a community with interest and expertise in the topic. Nevertheless, these guidelines do not result from a systematic and holistic literature review and are not meant to be used as a step-by-step guideline nor a prescription on how to achieve such desired changes. Rather, they are intended to be taken as a source of inspiration and best practices. Adopting each recommendation should be considered in relation to the context in which an initiative or project will operate and should be closely linked to its aims. CitiMeasure provided a unique opportunity for representatives of European cities, academia, and governmental and non-governmental organisationsto come together, discuss and identify how citizen science initiatives can change actors’ behaviour and enhance their policy impact. 5