Linos Cotsapas - Research Planning, Inc., Columbia, SC, USA and Pandion Technology, Ltd., Limassol, Cyprus
Jacqueline Michel - Research Planning, Inc., Columbia, SC, USA
Jason Hale - Pandion Technology, Ltd., Limassol, Cyprus,

The first environmental sensitivity index (ESI) maps were prepared days in advance of the arrival of the oil slicks from the Ixtoc 1 well blowout in the Gulf of Mexico in 1979. For almost 40 years, ESI maps have been specially developed for oil spill planning and response, with the first ESI maps in the Persian Gulf area developed for Kuwait in 1985. ESI maps incorporate a range of critical environmental data such as coastal and marine habitats, but ESI maps are not coastal habitat maps because: 1) the fundamental ESI shoreline classification is an integration of geomorphological and ecological states, and 2) ESI maps summarize data contained in a relational geodatabase, and thus can be used to analyse and display a much wider range of information than maps of coastal habitats. Worldwide, ESI maps have proven to be invaluable planning and conservation tools during oil spills and other marine emergencies by providing concise summaries of coastal resources that are at risk at a given time. However, design and use of ESI maps requires experience and expertise in coastal processes, ecology, and conservation and development planning so that the widest possible range ofrelevant information is effectively integrated.