This book is about a practical approach to the Mass Customization of complex products, services and software, namely "Configure-to-Order", the definition of modular product packages and their configuration on demand, to fit customer-specific needs. "Configure-to-Order" concepts apply equally well to configuring complex products, services, and software, and are relevant in industries ranging across manufacturing, public services, and financial services. The target audience is those interested in management or process improvement in areas such as customer service, sales, marketing, exports, new product development, or production. Software to support "Configure-to-Order" is discussed and a generic configurator evaluation checklist is provided. The objective is to provide the reader with a manageable approach to modularization and mass customization, the benefits of this approach, and the shift necessary to get there.