Creative Accumulation examines how nations build the capabilities required for sustained technological leadership, moving beyond simple catch-up growth. Drawing on Korea's long-term development experience, Jeong-Dong Lee introduces the concept of the "middle innovation trap", a condition in which countries achieve high levels of implementation capability yet struggle to generate original concepts, architectures, and design leadership.The book argues that original concept design is not the product of individual genius or sudden breakthroughs but the outcome of creative accumulation. Creative accumulation requires posing bold question, persistently accumulating trial-and-error experiences, and scaling up from ideas to viable outcomes. Integrating insights from innovation theory, evolutionary economics, and industrial policy, Jeong-Dong Lee shows how these processes of creative accumulation enable nations to become technology leaders.Although the book draws its evidence from the trajectory of Korean industry and technology, Korea's experience represents a compelling and instructive case of a broader developmental process. Drawing on decades of engagement with government and business, Lee shows that countries which fail to build solid implementation capability tend to fall into the middle income trap. Yet even countries that escape this may encounter the middle innovation trap if they fail to develop concept design capability, resulting in renewed stagnation. To transition out of this phase demands sustained, national-level efforts from firms, governments, and institutions. Creative Accumulation offers concrete policy prescriptions for overcoming the middle innovation trap, grounded in coordinated, mission-oriented, and long-term strategies that can guide nations at every stage of development.