Using the drivers-pressures-state-impact-responses (DPSIR) analytical framework, local stakeholder respondents and experts were interviewed to construct and prioritize a causality network that links ecosystem state of the coastal waters of Berau (East Kalimantan, Indonesia) with societal drivers of change. Particularly on the perceived top priority drivers and pressures, consensus among respondents was considerable. The constructed network was found to be consistent with literature findings from elsewhere in SE Asia. This causality network was then confronted with a local articulation of the SRES scenarios (IPCCs Special Report on Emissions Scenarios: A1, A2, B1, B2), and four plausible trajectories of future change were deduced over a period of 20 years, until 2030. Our scenario articulations differed greatly in the projected immigration influx into the region, in local economic growth and in institutional strength of governance. Under business-as-usual conditions, it is foreseen that fisheries will continue to overexploit the resource, and inland and mangrove deforestation, as well as sediment and sewage loading of the coastal waters, will increase, leading to declines in coral and seagrass extent and depleted fisheries. Scenarios with continued immigration (~A1, A2) will probably aggravate this pattern, whereas those with reduced immigration (~B1, B2) would appear to lead to considerable improvements in the state of the coastal waters of Berau. © 2011 The Author(s).