Book excerpt: The effective digitalization of business can make you a business leader; however, if not executed accurately, it can destroy your business too. Around 70 per cent of digital transformation projects have been failing. Even successful digitalization projects have become white elephants or expensive during the operations phase. Lean Digital Thinking introduces the '12-12-5 model'-12 lean digital thinking principles, 12 digital business building blocks and 5 lean digitalization phases-a brilliant guide that will enable business executives to become digital business champions. Leading digital expert, author VSR, as he is popularly known, introduces the world's first lean digital thinking philosophy with 12 principles to acquire a new digital mindset and throws in critical questions: Why digitalize? Where to digitalize? What to digitalize? And how at all to digitalize? He provides lean digital methods, templates and frameworks for digitalizing 12 business building blocks at an optimal cost. Further, new business models, products, services, processes, digital workplaces and operating models, driven by digital technologies, have been discussed with insights on how to leverage digitalization to get ready for the new normal that has emerged with the COVID-19 pandemic. An effective practitioner's guide, this is a must-read for business and technology executives and anyone wishing to master the art of digital business.