Abstract for book: This innovative Handbook presents a comprehensive overview of the significance of complexity theory for understanding institutions. Eminent scholars cover the key tools and concepts of the field, including emergence, networks, ergodicity, and modularity, exploring their contributions to institutional formulation and evolution. Abstract for chapter: The bulk of dynamical models in economic theory are ergodic. Behavioral models constructed using expected utility theory, including all standard macroeconomic models, are ergodic. However, models must exit ergodicity to explain creative social phenomena like institutional emergence, self-organization, innovation, and catallaxy. Achieving theoretical escape velocity from ergodicity is no easy matter, but promises a rich new frontier to explore the formation, sustenance, and breakdown of economic institutions. This article is organized as an exposition for researchers new to ergodic theory and issues surrounding ergodicity and institutional economics.