ITIL is the acronym for the "IT Infrastructure Library" guidelines developed by the CCTA (now OGC) in Norwich, England, for the British government.

Today, ITIL is the de-facto global standard in the area of service management. It contains comprehensive publicly accessible specialist documentation on the planning, provision and support of IT services. ITIL provides the basis for improvement of the use and effect of an operationally deployed IT infrastructure.

IT service organisations, employees from computing centres, suppliers, specialist consultants and trainers took part in the development of ITIL. ITIL describes the architecture for establishing and operating IT service management.

The internationally recognized ITIL®-logo has adorned the covers of ITIL® books for years. The familiar diamond consisting of a number of smaller diamonds is now internationally well-known.

But very few people remember the original meaning of the logo. ITIL® supporters from the very beginning asserted that the diamond symbolizes the coherence in IT infrastructure. They believe the four fields represent the four main subject areas in ITIL®: Service Support, Service Delivery, Infrastructure Management and IT Management. However, the square fields around a central area 'service provision' also symbolize the four parties involved in the ITIL® standard: in the center ITIL® literature (with OGC as owner), around the center the users (represented by ITSMF), the examination institutions (e.g. EXIN) and finally the trainers and suppliers of ITIL® related services.