Marine protected areas (MPAs) are spatially defined marine units in which one or more human activities – particularly fishing – are restricted or prohibited. They represent a precautionary and ecosystem-based approach to ocean management (Mangel 2000; Pikitch et al. 2004; Jones 2006). The 1992 Convention for Biological Diversity set a target for 10% of the global marine area to be designated as MPAs by 2010. Progress with designating MPAs is, however, slow, MPAs covering just 1.3% of the marine area and 3.2% of marine areas under national jurisdiction. Consequently, the deadline was recently extended to 2020. Nonetheless, in the past two decades there has been a rapid increase in MPA research and implementation throughout the world. If the governance of MPAs is improved in ways we describe here, MPAs and other place-based approaches will continue to be important tools for the management of marine resources.