The ‘Western’ green movement has grown rapidly in the last three decades: green ministers are in government in several European countries, Greenpeace has millions of paying supporters, and green direct action against roads, GM crops, the WTO and neo-liberalism, have become ubiquitous. The author argues that ‘greens’ share a common ideological framework but are divided over strategy. Using social movement theory and drawing on research from many countries, he shows how the green movement became more differentiated over time, as groups had to face the task of deciding what kind of action was appropriate. In the breadth of its coverage and its novel focus on the relationship between green ideas and action, this book makes an important contribution to the understanding of green politics.