'Nash's existence theorem tells us that every finite game has at least one (mixed) Nash equilibrium. But how might players reach such an equilibrium? Christian Kroer's Games, Markets, and Online Learning provides both the background necessary to study this question and the first textbook treatment of a range of modern and important topics, including convergence rates for self-play, security games and their applications, and the approximate fair division of indivisible goods.' Tim Roughgarden, Columbia University 'AI and optimization drive the Internet economy - think automated pricing and allocation through Uber, YouTube, Alibaba, Amazon, Tencent, and hundreds of other two-sided marketplaces. Generative AI increasingly relies on the same fundamental techniques to push the frontier of reasoning and agentic decision-making. In this book, Christian Kroer introduces that intersection of economic thinking, machine learning, and optimization - for the first time, and from the ground up. This is a foundational work for those looking to understand the modern technology-first economy.' John P. Dickerson, CEO, Mozilla AI 'This book presents an exciting panorama of recent results in market algorithms and mechanism design. It offers a comprehensive exposition, taking readers from the real-world motivations that make these problems relevant, through the underlying mathematical concepts, and into clear and polished proofs. An excellent read for staying at the forefront of these rapidly advancing fields.' Nicolas Stier-Moses, Meta Central Applied Science