This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book brings together four contributions on how social movements mobilize around land and resources and how they have in fact exercised this institutional imagination, drawing inspiration from the approach to law and social movements that one of us has taken. The high volatility of agricultural markets since the mid-2000s, culminating in the global food price crisis of the spring of 2008, is explained by the growing pressures on land and by fears concerning the scarcity of resources relative to a rise in demand for food of course, but also for fuel and fiber. The government considered these farms to be its own property, which could be sold to private investors or foreign states, to groups depending on communal lands and to indigenous groups, who depended on the products of the forests.