This paper presents a computer-aided technology for the synthesis of environmentally benign materials with optimal properties. The approach combines stochastic optimization and group contribution methods. Stochastic optimization is in the form of the Simulated Annealing algorithm and is used to search and select chemicals of desired performance. The paper discusses the representation schemes and the synthesis algorithm developed for molecular design. The proposed synthesis technology is extended to problems related to environmental concern and the applications include examples of solvent design. In these studies, the requirements for advanced performance address separation-enhancing properties alongside with environmental behavior.