This book integrates the findings of group research emphasizing “Madness of the Crowd” versus collective intelligence that highlights “Wisdom of the Crowd.”  Thus it  provides an overview of psychological research on group processes and collective intelligence, analyzing cognitive, social, and structural factors. Chapters address applications of this research to contexts such as organizations and online behavior, and offer guidelines and hands-on demonstrations of psychological principles. The book is highly relevant  to students and instructors in personality and social psychology.