The French Hydrographic Office has developed, for its own needs, very powerful computer tools to assit its cartographic work. This software, which is used at all stages of chart making, has been set up in two main phases, backed by ultra-modern computer technology affording maximum ease of use for the cartographer. The modular nature of the software that has been developed ensures that the tools are well adapted to future developments in computer equipment and makes it possible to adapt it, where necessary, to other cartographic work besides nautical charting.