We examine the social resistance against large dams as environmental justice movements in four case studies - the Sardar Sarovar Project from India, the Hidrosogamoso from Colombia, the ‘new water culture’ movement in Spain, and the Lesotho Highlands Project from Lesotho - with diverse social, political and environmental contexts. We discuss three broad issues. First, the nature of the involvement of civil society and metropolitan intelligentsia in leadership roles. Second, how cross-class and multi-sectoral alliances have been forged between the local and the global. And third, how the notion of environmental justice in relation to social justice is adopted in these movements.