This study was supported by the country representatives of the Marine and Coastal Biodiversity Managementin Pacific Island Countries (MACBIO) project. We particularly thank in-country experts who helped refine and finalise the marine bioregions for use in their respective countries. MACBIO was funded by the German Federal Ministry for the Environment, Nature Conservation, Building and Nuclear Safety's (BMUB's) International Climate Initiative (IKI). It was implemented by the Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) with the countries of Fiji, Kiribati, Solomon Islands, Tonga and Vanuatu. It had technical support from the Oceania Regional Office of the International Union for the Conservation of Nature (IUCN) and worked in close collaboration with the Secretariat of the Pacific Regional Environment Program (SPREP). Significant assistance with data provision was provided by the following people and institutions: National Oceanic and Atmospheric Administration; Reef Life Survey; Secretariat of the Pacific Community (SPC); Secretariat of the Pacific Regional Environment Programme (SPREP); The Nature Conservancy (TNC); UNEP-WCMC; WorldFish Centre; World Resources Institute (WRI), Gerry Allen, Simon Donner (UBC), Maël Imirizaldu (Marine Conservation Consulting), Stuart Sandin (Scripps Institution of Oceanography), Karen Stone (Vava'u Environmental Protection Association), Paul Muir (Museum of Tropical Queensland), Yashika Nand and Waisea Naisilisili (Wildlife Conservation Society Fiji), Peter Houk (University of Guam) and the Micronesia Coral Reef Monitoring program, Emre Turak, and Kate Fraser, Badi R Samaniego, Janet Eyre working with the Khaled bin Sultan Living Oceans Foundation. We are further grateful to the University of Queensland and the University of Leeds for assistance with administration, and to Geoscience Australia for releasing Mr Sullivan for this project. The report benefitted from comments by Mark Spalding and Piers Dunstan, and the help of Roopinder Nagra.