Web Services are a keystone of the Enterprise architecture. Many services are exposed by Enterprise Server and are defined in documents (WSDLs). Client applications communicate with Enterprise Server through services. A client can be any of the Enterprise applications such as InDesign or Content Station, but could also be your custom client applications that you are about to develop in order to integrate Enterprise. This section explains how this all comes together and gives an introduction of Enterprise services: a good starting point for integrators.