Introduction

Obstructive Direct Action (ODA) is a practice involving the use of disruptive tactics which physically impede movement and work by others to achieve social, environmental, and political goals. It is a practice that is widely used by social and labour movements. This book concerns itself with a series of environmental blockades, which played a critical role in establishing and shaping ODA as a key response to threats to biodiverse places from 1979 onwards. This chapter presents key and novel concepts regarding ODA and explains why a focus on environmental campaigns carried out between 1979 and 1990 in Australia, the United States, and Canada are key to understanding the historical and contemporary use of the practice in a range of movements. It also explores common goals and outcomes in ODA-based campaigns and a range of influences that impact upon strategic and tactical choices, innovation, and diffusion.