The Information Technology Infrastructure Library (ITIL) is a well established process model for the operation of IT services. It was initially created by ITIL was originally created by the CCTA, a UK Government agency in a long term collaboration of partners in the British IT industry. It is published by the Office of Government Commerce (OGC).

ITIL is composed of a set of books, describing together all important aspects of IT service management. They are used to aid the implementation of a lifecycle framework for IT Service Management. This customizable framework defines how Service Management is applied within an organization. It also aligned with the international standard, ISO 20000 - Service Management (derived in part from the earlier BS standard). It is currently published as version 3.

ITIL is organized into a series of volumes including: Service Strategy, Service Design, Service Transition, Service Operation and Continual Service Improvement. These together describe a feedback system throughout all areas of the IT service lifecycle. The volumes provide a framework of good and best practice disciplines that enable IT Services to be provided effectively.

The ITIL Toolkit is a collection of resources brought together specifically to accompany ITIL. The materials included are intended to assist in both understanding and implementation.

ITIL and supporting documents provide a number of features:

• Sets of processes various IT areas.
• Guidance on process establishment.
• Feedback on implementing and improving the IT service processes.

ITIL is also useful when specifying Service Level Agreements (SLAs) for IT service provision.

Combining ITIL with process assessment such as ISO/IEC 15504 and CMMI provides an improvement framework that can result in continual improvement of IT. The ISO committee for ISO/IEC 15504 is currently looking at a specific variant incorporating ITIL as a Process Reference Model. Read more about ITIL and process assessment in the author's books.

We have worked with IT processes and SLAs since the introduction of ITIL.

ITSM is Information Technology Service Management. This covers the processes associated with delivering IT services. There is currently work occuring within the ISO SC7 working group for ISO/IEC 15504 to create a process assessment model for ITSM.