In this paper, an Integrated Computer Aided System (ICAS), which is particularly suitable for solving problems related to integrated design of chemical processes; is presented. ICAS features include a model generator (generation of problem specific models including model simplification and model reduction), a simulator (use of problem specific simulation strategies for steady state and dynamic simulation), toolboxes (thermodynamic toolbox, synthesis toolbox, control toolbox, design toolbox and analysis toolbox), and an interface for problem defintion. Each toolbox solves aspecific set of problems and communicates with all other computational tools available in ICAS. A large range of thermodynamic models for estimation of the necessary thermo-physical properties, a large range of computational algorithms for determination of various types of phase diagrams, algorithms for process synthesis, design, control form the basis for the toolboxes. The available features of ICAS are highlighted through a case study involving the separation of binary azeotropic mixtures. (C) 1997 Elsevier Science Ltd.