Mainstreaming citizen science in policy: Adaptations needed in policy and how to achieve them in five European countries

The potential of citizen science remains underutilised in conventional policy practice for various reasons – a compelling one being that the policy system itself must adapt to leverage this potential. This paper aims to explore what mainstreaming citizen science in policy entails and how it can be realised. We define mainstreaming as the ongoing, incremental processes of creating and re-forming the institutional conditions that enable policy-making to operationalise and incorporate citizen science. We focus on identifying 1) the contributions of citizen science to policy-making and the challenges for leveraging these contributions, and 2) mainstreaming strategies to create the institutional conditions that enable the uptake of citizen science in environmental policy. Through case studies conducted in five European countries (Italy, Netherlands, Norway, Spain, United Kingdom), we generate contextualised and synthesised insights across different policy contexts. Our findings highlight the potential of mainstreaming citizen science to enhance environmental policy-making, enabling it to address complex societal challenges more effectively and equitably. Citizen science marks new modalities of public engagement, which change the roles and relations between policy-makers, scientists and citizens, shifting these towards becoming collaborators and co-creators. This requires also changing the processes by which policy problems and solutions are defined, implemented and monitored, as well as the underlying structures and resources that support the uptake of such processes by policy-makers.