IT out sourcing service providers are increasingly being challenged to reduce costs while improving the quality of service implementation and delivery. A key contributor to those goals can be an improved methodology for services solution engineering - which involves analysis of the client's requirements and environment, mapping the information to the capabilities of the service provider, documenting the design and implementation of each service, and defining transformations of the customer's environment to the target IT infrastructure defined by the overall design that facilitates more efficient service delivery. One such improved methodology leverages reuse, in the form of a taxonomy of standardized service offerings and a repository of standardized service designs they can be mapped to. In this paper, we describe a prototype system that provides automation for such a methodology by encoding design policies that are used to assist the services solution architect gather relevant information from the customer and cross check design decisions. The approach demonstrates how the notion of computer-aided design can be applied to the world of IT services and introduced in an incremental manner. This paper presents the system architecture, discusses the sources and models of knowledge, and illustrates how this knowledge can be used with specific examples from the services field.