Our knowledge of the oceans is increasing rapidly, as more powerful tools for exploration and exploitation make it easier to locate valuable resources, such as fish stocks, oil and gas reserves, or sites for wind and hydropower schemes. At the same time competition for space has intensified, affecting marine life and people's livelihoods. Much has been written about marine management using marine protected areas, but MPAs are only a small subset of spatial management tools available. MPAs and MPA networks are better seen as starting points for more comprehensive spatial management,...