This book describes multi-attribute decision-making (MADM) methods and provides stepwise guidelines in applying those methods. The authors describe the most important MADM methods, with an assessment of their performance in solving multiple problems encompassing several fields. This book contains 12 chapters, and an additional appendix on weight assignment methods. Chapter 1 provides an overview of decision-making and its fundamental concepts. Each of chapters 2 through 12 is devoted to a separate MADM method. In total, some 20 MADM methods are presented in the book. The chapters are arranged according to pedagogical purposes, so the audience can easily engage with the presented materials found in each chapter. The authors’ intent is that each chapter can stand alone. To do this, they provide the audience with a brief description of the materials and methods required to cover every aspect and mathematical concepts pertinent to each presented method. Dedicated readers may go through the entire book to gain a deep understanding of MADM methods and their theoretical foundations. Others may choose specific chapters without facing any difficulty understanding their respective MADM methods. Each chapter, which describes a specific MADM method, or in some instances a family of methods, starts with a brief literature review of the methods’ development, followed by a description of the its theoretical foundation. The philosophical basis of each method is reviewed and mapped to the mathematical framework of each MADM method. Lastly, a stepwise description of each method that serves as the guideline for its implementation to cope with real-world MADM problems is also presented.