ITIL® is the only consistent and comprehensive documentation of best practice for IT Service Management. Used by thousands of organisations around the world, a whole ITIL philosophy has grown up around the guidance contained within the ITIL books and the supporting professional qualification scheme.

ITIL consists of a series of books giving guidance on the provision of quality IT services, and on the accommodation and environmental facilities needed to support IT. ITIL has been developed in recognition of organisations’ growing dependency on IT and embodies best practices for IT Service Management.

The ethos behind the development of ITIL is the recognition that organisations are becoming increasingly dependent on IT in order to satisfy their corporate aims and meet their business needs. This leads to an increased requirement for high quality IT services.

Overview and Benefits
ITIL provides a systematic and professional approach to the management of IT service provision. Adopting its guidance offers users a huge range of benefits that include:

• reduced costs
• improved IT services through the use of proven best practice processes
• improved customer satisfaction through a more professional approach to service delivery
• standards and guidance
• improved productivity
• improved use of skills and experience
• improved delivery of third party services through the specification of ITIL or ISO 20000 as the standard for service delivery in services procurements.

Source: ITIL Official Website