Book excerpt: In recent years, environmentalism in the US has increasingly emerged at the community level, focusing on local ecological problems. Correspondingly, the American environmental movement has exhorted its supporters to 'think globally' but 'act locally'. The authors examine this modern environmental mantra by analysing the opportunities and constraints on local environmental action posed by economic and political structures at all levels. The difficulties involved in local activism are explored in three case studies - a wetlands protection project, water pollution of the Great Lakes, and consumer waste recycling. The final chapter then reflects on the challenges facing citizen-worker movements in each case study, and concludes that, despite the inherent difficulties, any successful attempt at mobilisation must have a local component.