As countries consider new area-based conservation targets under the Convention on Biological Diversity, protected areas (PAs) and their impacts on people and nature are coming under increasing scrutiny. We review the evidence base on PA impacts, combining the findings from existing rigorous impact evaluations with local case studies developed for this study. We identify characteristics of PA establishment and management that improve the sustainability of biodiversity conservation and justice for local communities. We find that recognizing and respecting local values and knowledge about natural resource stewardship, colearning, and comanagement are key to achieving positive impacts for nature and people. Transforming PA governance toward more inclusive conservation depends upon the ability of PAs to be designed and implemented around the values and needs of local people.