COVID-19 is the virus that proved the fragility of the world. It took only the simplest form of life to shake the connectivity and dependency of society. This book is a real-time record and recommendation from a community of complexity scientists reacting to the pandemic. Through nontechnical articles, interviews, and discussions spanning the early days of the pandemic through the fall of 2021, researchers seek ways to stay responsive to complexity when every force conspires toward simplicity. The Complex Alternative encompasses immunology, epidemiology, psychology, inequality, and collapse. It is an effort to preserve perspective at a time when partiality seeks dominion. Edited by David C. Krakauer and Geoffrey West, this book features the thoughts of more than sixty members of the Santa Fe Institute's research community on the future of complexity science and the broader significance of science in the twenty-first century.