At the beginning of the century marked by economic normalization and political inaction several social phenomena have given the fret with the most catastrophist expectations about the future of citizen participation. Since this revitalization of social participation, this work tries to analyze social movements in the current, both economic and political context, in its individual idiosyncrasy and its internal functioning. Both the reader initiated and the one who tries to approach for the first time this decisive phenomenon of the global society that are social movements will find a set of work on their pages that will help, from a broad and plural perspective, to improve their knowledge about what they are , how they work and what can we expect from these collective behaviors such as important to the 21st century incipient.