To provide better service to customers and remain competitive in the business environment, a wide variety of ready-to-use software and technologies are available for one to “grab and go” in order to build up software systems at a rapid pace. Currently, a wide variety of Web services are available and ready to use for this purpose. Current software process models also support commercial-off-the-shelf (COTS)-based development processes. However, although COTS and Web Services are similar, they are different in many perspectives. On one hand, there are various software process models that support Web services development. Yet there is no process model that supports the project that uses services provided by others. This chapter introduces the Incremental Commitment Spiral Model (ICSM), a new generation process model that provides development guidelines, from exploring a Web service alternative to deployment and maintenance with case studies.