Book excerpt: The science of complexity has revolutionized our understanding of everything from the brain to the economy to the weather. This book shows how it can change the way we approach our most persistent social problems. It introduces key concepts like emergence, self-organization and networks, and uses them to propose novel solutions to problems that affect us all. Suitable for anyone struggling to cope with complex challenges. Written by Yaneer Bar-Yam the leading expert in the use of complexity science in solving real world problems in healthcare, education, military, engineering, ethnic violence and terrorism.