MTDA Agency started to develop the first forest fire simulator in 1991. It is designed for the context of the French Mediterranean region and according to the requirements of its users. The simulator is designed using architecture with three axes: a user friendly interface with numerous functions; a fire spread model using the latest research achievements; a database whose structure, contents and updating govern the rapidity and quality of the simulations. The simulator was developed under UNIX with respect of the rules of the main standards (C language, XWINDOW, OSF Motif) It is available for SUN 4 (SPARC processor). The first results are very encouraging and numerous applications are currently being developed.