The primary goals of this book are to present the basic concepts and principles of mathematical programming in terms of set-valued analysis (Chapters 2 and 3) and on the basis of the method of approximation, to develop a comprehensive optimality theory of problems described by ordinary DFI) (Chapters 2, 3 and 4). This book consists of four chapters divided into sections and subsections and contains many results that have not been published in the monographic literature.