Over the past century, the twin fields of mass psychology and collective behaviour socioogy have shared a rather marginal and episodic existence. They used to focus on crowd events and social movements, but they seem to have lost ground. The author gives them new relevance and topicality by re-connecting them with some of the very latest findings from biology (social genes), neurology (mirror neurons), and social science (reproducing memes).Through ten ever widening concentric circles, he takes us on a fascinating journey, from gregarious individuals to small groups, performance audiences and social movements, organizational culture and social networks, mass media and product markets, public opinion, and finally contemporary internet research.He notes that both managers and policymakers are increasingly surprised by mental earthquakes and tsunamis suddenly rippling around the globe within mere minutes.