Description : The widespread experience of environmental impact assessment (EIA) as an anticipatory environmental management tool has generated a considerable debate over the extent to which it is achieving its purposes. This has been measured in terms of EIA ‘effectiveness’, especially as discussion has moved away from issues of procedural implementation, to the more substantive goals of EIA and its place within broader decision-making contexts. Empirical studies have revealed the relatively weak degree of influence on planning decisions that is being exerted by EIA, which is increasingly being attributed to its rationalist beginnings. This article seeks to direct this debate towards the founding political purposes of EIA which, it is argued, provide a neglected, yet strong, basis for EIA reform. A number of illustrative suggestions are made as a result of this redirection, to enable EIA to adopt a more determinative role in decision making and to contribute to more sustainable patterns of development planning.