This book focuses on operations management methods for analysing complex systems from a system engineering perspective. It presents various advanced multi-criteria decision analysis methods for investigating factors that influence complex systems. In turn, it shows how to improve systems' performance, including their competitiveness, safety, and sustainability. The book also draws on examples of typical virtual systems such as tourism, aviation maintenance, and waste-to-wealth systems to illustrate the operations management methods discussed. Cases from day-to-day life are used to elicit heuristic questions on the operations management methods presented in each chapter.  The book will help researchers, operations managers, and engineers alike to understand the latest advances in operations management methods for analysing complex systems from the standpoint of system engineering.