The “Open Air Laboratories” (OPAL) is a large, England-wide environmental public engagement (PE) project based on the “citizen science” model. It is designed to involve people of all backgrounds and abilities in the production of environmental science and in the process to educate and raise awareness and enthusiasm about nature and its importance. This paper draws on a series of interviews with scientists and science communicators involved in the project to explore their motivations and aims for the project and what they see as the goals of public engagement generally. We find a varied and nuanced array of motivations and aims that interviewees cite for taking part in the project, pointing towards a re-evaluation of traditional ways of understanding the value of public engagement, policy-relevance and dialogue within public engagement. Especially relevant in relation to thinking about the policy-relevance of PE is our conclusion that there are many different ways of thinking about the value of PE, characterised in this paper as “the neglected middle”
