This book explores the process of popular mobilisation in contemporary Mexico through the experience of the country's most important popular organisation - the teachers' movement. It creates a distinctive perspective on Mexican politics and makes an original contribution to the study of popular or 'social' movements. This is the first in-depth study of a popular movement anywhere in Latin America, providing a richly detailed account of its organisation, leadership, strategic choices, and factional divisions. Through its innovative methods, which produce an unusual and compelling blend of fact and theory, the book uncovers the motivations and mechanisms of popular mobilization, as well as explaining its interactions with national politics in Mexico and beyond.