PDE (Plant Design Expert)is an intelligent shell that creates a GT PRO input file based on the user's requirements for the proposed plant. It then runs GT PRO in the background and displays abbreviated output results. PDE takes away much of GT PRO's flexibility and replaces it by a high degree of automated, expert logic, deciding what type of cycle should be used, its configuration details and the numerical values of its design parameters. PDE provides its user with approximately fifty adjustable inputs to state his/her requirements. The rest of GT PRO's several thousand inputs are generated automatically.