"Participatory research in which experts and non-experts are co-researchers in addressing local concerns (also known as participatory action research or community-based research) can be a valuable approach for dealing with the uncertainty of social-ecological systems because it fosters learning among stakeholders and co-production of knowledge. Despite its increased application in the context of natural resources and environmental management, evaluation of participatory research has received little attention. The objectives of this research were to define criteria to evaluate participatory research processes and outcomes, from the literature on participation evaluation, and to apply them in a case study in an artisanal fishery in coastal Uruguay. Process evaluation criteria (e.g., problem to be addressed of key interest to local and additional stakeholders; involvement of interested stakeholder groups in every research stage; collective decision making through deliberation; and adaptability through iterative cycles) should be considered as conditions to promote empowering participatory research. Our research contributes to knowledge on evaluation of participatory research, while also providing evidence of the positive outcomes of this approach, such as co-production of knowledge, learning, strengthened social networks, and conflict resolution."