'Much of the world thinks in terms of village-like groups and individuals, when in reality they're operating in social networks. That's why the Covid-19 virus spreads so quickly. Few people live in tight bubbles – they maneuver among overlapping partial networks of friends, family, neighbors, schools, and work. This myth-busting book is a masterpiece – brilliantly showing the impact of personal networks in our lives. Its unique format shows the path-breaking development of the network perspective – by linking classic readings and current research into community, cognition, culture, social capital, social movements, work, inequality, and social media.' Barry Wellman, FRSC