ITIL is now in many ways bigger than its "master" — IT service management. From its origins in the UK government, its use has grown rapidly in the last decade and ITIL continues to dominate corporate thinking in IT operations, IT support, and IT service delivery. There are many benefits to ITIL adoption, particularly productivity, service quality, business reputation, and cost savings. However, ITIL is fraught with adoption challenges that could be prevented, or at least minimized. This report helps IT infrastructure and operations (I&O) professionals plan for ITIL success by understanding what commonly goes wrong and best practices to employ to mitigate these risks.