1999 0-7734-3202-7 The work examines the new graphic computer-based approach to the selection of efficient preferable decisions from an infinite number of feasible decision alternatives. The approach, which is based on the mathematical theory of approximation of multi-dimensional bodies, develops the ideas of the goal method and of the multiple criteria decision making. Mathematical foundations and environmental applications of the approach are described. Integration of the approach with modern information technologies is considered. Applications via computer networks are discussed. The book can be used by graduate and postgraduate university students. Large part of the book is written in a simple form and can be assessed by any computer-literate person.