Geo-information technology can be useful in Integrated Coastal Zone Management (ICZM). The benefits lie in the fact that geo-information technology can process large amounts of spatial data and can integrate different types and sources of data. The general aim of this paper is to demonstrate these benefits. First, we argue that spatial databases and GIS can be used and are present in most of the policy analysis phases of ICZM. Then, we illustrate this with a case study about seagrass beds in Banten Bay, Indonesia. The development of a spatial database, including seagrass maps is described. An overlay analysis shows that the largest and most dense fields of seagrass, which are also the most important as habitat for commercial fish species, are located near past and planned shoreline developments. This and similar type of spatial analyses are very important to support ICZM decision-making at the district level. A good spatial information infrastructure to collect data and make this data accessible is a pre-requisite. © 2003 Elsevier Science Ltd. All rights reserved.