Computer aided design of chemical plant. The effort necessary for computing and design of a chemical plant as well as the preparation of documentation has increased. This is a result of the growing complexity of process design in order to satisfy economic criteria and more stringent safety and environmental requirements. The available time is limited. CAD is one of the tools that assists the plant designer by solving all these requirements. Even at the very beginning of the development of digital computers, their possibilities in graphics electronic data processing were recognized. Since the 1970s, CAD has been utilized in plant design. The use of two‐dimensional or three‐dimensional CAD software is possible. In most cases this is done by using self‐contained dedicated solutions. The integration of the applications promises an increase of productivity. To reach this aim a database management system (DBMS) may be useful. DBMS is also useful as an interface to other computing tools like FEM‐ or process flowsheeting programs. The development of the soft‐ and hardware domain has reached a level of sophistication which makes the economic utilization of CAD possible. Nevertheless, much work still remains to be done.