The document provides a 5-step process for defining IT services based on the Shared Information and Data (SID) model from the Telemanagement Forum (TMF). The 5 steps are: 1) select an enterprise product and identify supporting IT services, 2) list all related IT systems, 3) mark IT services as customer-facing (CFS) or resource-facing (RFS), 4) map RFS to CFS, and 5) identify the resources that make up RFS. Defining services using this process helps connect products to CFS and moves the IT organization closer to the end-customer.