This ebook on service modularity responds to the growing demand for architectural and design knowledge focusing on service offerings and service business.Modularity has intrigued researchers for many years (Starr, 2010) and can be traced back to the early work of Simon (1962) who, in developing a general systems theory, argued that hierarchical decomposition of systems can lead to the reduction of complexity. Since then there has been a substantial development of our understanding of modularity across many dimensions, but with the prime focus on the architecture of manufactured products. Sanchez (1999) elaborated on the systems view of Simon (1962), and Ulrich (1995, p. 419) saw the interfaces between components as "the scheme by which the function of a product is allocated to physical components". Architecture is a broader concept that includes product modularity, component complexity, product platforms, loosely coupled interfaces, component commonality and number of components (Fixson, 2005). Product architecture decisions are closely related and include the way that systems are decomposed, the selection of components to be used, and the way that these components are aligned with one another (Mikkola, 2006). Despite the rapid growth of modularity research, the research has been almost exclusively confined to the assembled products context and, seemingly, it is expected that the principles of product modularity apply in the services context (e.g., Schilling, 2000).