Participatory action research (PAR) is an approach for fully co-creating research into environmental problems with the public. We argue this is mostly done for manifest environmental problems that clearly threaten livelihoods and have highly predictable impacts. But the conventional PAR approach is not suitable when the impacts are poorly understood and pose a low threat to livelihoods. Such latent environmental problems do not have a clear conflict to be resolved; instead, the community’s inertia should be overcome. In this article, we develop what we call the PAR-L approach, for which we present a step-by-step guide and an evaluation framework. We then demonstrate this approach on the latent problem of the invasive alien Coralita vine (Antigonon leptopus) on Saba (Caribbean Netherlands) and find that it results in thorough understanding of the community inertia. Overcoming the inertia would require a project to run longer and a simultaneous knowledge-gathering effort, but PAR-L is a good starting point.