This document provides an overview of ITILv3 and its key concepts. ITIL is a framework for IT service management best practices that focuses on aligning IT services with business needs. Version 3 simplified the framework into 5 core publications and placed more emphasis on strategic guidance. The service lifecycle consists of 5 stages: service strategy, design, transition, operation, and continual service improvement. The goal is to design, transition, and operate services that meet business requirements and strategic objectives.