Collaborative research prioritization (CRP) studies have become increasingly popular during the last decade. By bringing together a diverse group of stakeholders, and using a democratic process to create a list of research priorities, these methods purport to identify research topics that will better meet the needs of science users. Here, we review 41 CRP studies in the fields of ecology, biodiversity conservation and environmental science that collectively identify 2031 research priorities. We demonstrate that climate change, ecosystem services and protected areas are common terms found in the research priorities of many CRP studies, and that identified research priorities have become less unique over time. In addition, we show that there is a considerable variation in the size and composition of the groups involved in CRP studies, and that at least one aspect of the identified research priorities (lexical diversity) is related to the size of the CRP group. Although some CRP studies have been highly cited, the evidence that CRP studies have directly motivated research is weak, perhaps because most CRP studies have not directly involved organizations that fund science. We suggest that the most important impact of CRP studies may lie in their ability to connect individuals across sectors and help to build diverse communities of practice around important issues at the science–policy interface.