Every major enterprise has a significant installed base of existing software systems that reflect the tangled IT architectures that result from decades of patches and failed replacements. Most of these systems were designed to support business architectures that have changed dramatically. At best, these systems hinder agility and competitiveness and, at worst, can bring critical business functions to a halt. Architecture-Driven Modernization (ADM) restores the value of entrenched systems by capturing and retooling various aspects of existing application environments, allowing old infrastructures to deliver renewed value and align effectively with enterprise strategies and business architectures. Information Systems Transformation provides a practical guide to organizations seeking ways to understand and leverage existing systems as part of their information management strategies. It includes an introduction to ADM disciplines, tools, and standards as well as a series of scenarios outlining how ADM is applied to various initiatives. Drawing upon lessons learned from real modernization projects, it distills the theory and explains principles, processes, and best practices for every industry.