IT as a service (ITaaS) is an operational model where the IT organization of an enterprise run much like business, acting as a distinct business entity creating products and services for other Line of Business (LOB) organizations within the enterprise. At its core, ITaaS is a competitive business model where an enterprise IT organizations has to compete in order to be the provider to the needs of the LOBs. Other options other than the internal IT organization may include outsourcing companies and public cloud providers.

Under an ITaaS model, the internal IT organization of an enterprise will have a business-centric focus. It will place great emphasis on the needs and the outcomes required by the LOBs. The benefits to the enterprise sought by using the ITaaS model are standardization and simplification of products delivered, improved financial transparency and more direct association of costs to consumption, and increased IT operational efficiency. The transformation of an internal IT organization from operating as a cost-center to an ITaaS model is also believed to produce improved levels of business agility for the enterprise as a whole.