Mathematical Modeling using Fuzzy Logic has been a dream project of the author. Fuzzy logic provides a unique method of approximate reasoning in an imperfect world. This text is a bridge to the principles of fuzzy logic through an application-focused approach to selected topics in Engineering and Management. The many examples point to the richer solutions obtained through fuzzy logic and to the possibilities of much wider applications. There are relatively very few texts available at present in fuzzy logic applications. The style and content of this text is complementary to those already available. New areas of application like application of fuzzy logic in modeling of sustainability are presented in a graded approach in which the underlying concepts are first described. The text is broadly divided into two parts which treat Processes, Materials and System Applications related to Fuzzy Logic and then the second part delves into the Modeling of Sustainability with the help of Fuzzy Logic. The book offers comprehensive coverage of the most essential topics, including: Treating Processes, Materials, System Applications related to Fuzzy Logic Highlighting new areas of application of fuzzy logic Identifying possibilities of much wider applications of fuzzy logic Modeling of Sustainability with the help of Fuzzy Logic. The level enables a selection of the text to be made for the substance of undergraduate, graduate and post graduate level courses. There is also sufficient volume and quality for the basis of a postgraduate course. A more restricted and judicious selection can provide the material for a professional short course and various university level courses.