ITIL is the buzzword that represents the new wave of transformation that has been launched in IT organizations across the world. It is the new Six Sigma, SEI/CMM, COBIT and BPR that is directed at making an IT organization more effective. While you hear a lot about ITIL, it is really the underpinnings of a new philosophy of IT--service management.
Service management is where IT offers standardized services to its customers and delivers them in an effective, continuously improving fashion. ITIL is the framework of processes that powers service management (ITSM). Service management is a powerful concept as it focuses on how the end user of IT services interacts with IT, and it aims to deliver services in a customer-friendly way with a focus on creating the right balance between cost, quality, and risk. Service management is the optimal business model for IT as it optimizes the value chain on what is truly important--the customer.
Many people ask “Why ITIL?” as opposed to any of those other aforementioned process improvement efforts. The primary reason is because ITIL is focused on IT alone and integrates many of the concepts of business process reengineering and Six Sigma to deliver a comprehensive framework for delivering IT services. ITIL is the language that provides the transparency and foundation that can weave together all the things that IT
"Impartial observers from other planets would consider ours an utterly bizarre enclave if it were populated by birds, defined as flying animals, that nevertheless rarely or never actually flew. They would also be perplexed if they encountered in our seas, lakes, rivers and ponds, creatures defined as swimmers that never did any swimming. But they would be even more surprised to encounter a species defined as a thinking animal if, in fact, the creature very rarely indulged in actual thinking."