The CERN Service Catalogue is an inventory of all services that CERN offers to users. It is the list of WHAT services are available to users. Services are organized in a three level hierarchical structure.

1. Service Areas, the top level. A service area is simply a placeholder that groups customer services which have related scope and user communities.
2. Customer Services, the second level, which groups services together that have closely related scope and user communities. On the customer service level we have assigned the role of service owner.
3. Service Elements, On the service element level we find a clearly defined service, with a scope, with information on when the service can be used and when support is available, etc..

These service, that are available to users, are depending on tools, functions, and activities provided and supported by the sections and groups at CERN. So CERN groups provide Functional Elements, that support user services. On the functional elements, we have assigned the role of Functional Service Manager

The service catalogue contains these relationships which identify the dependencies between the tools, and activities in the groups, and the services provided to the users.

The relationship between WHAT services are available, and HOW these services are provided through the use of functional elements. (here you can find more information on the service structure)