Interest shown on the environmental impact of operations of multinational enterprises in developing countries has grown significantly recently, and has fuelled a heated public policy debate. In particular, there has been interest in the environmental degradation of host communities and nations resulting from the operations of multinational oil companies in developing countries. This article examines the issue of environmental costs and responsibilities resulting from oil exploitation and production in the Niger Delta region of Nigeria. The case study is based, in part, upon series of interviews with key stakeholders in the Nigerian oil industry. The article further examines the implications of the current practice and policies of multinational oil companies with respect to environmental impact of oil exploitation. The study’s findings illustrates that it is becoming increasingly apparent to oil companies that pollution prevention pays while pollution does not and under pressure from stakeholder groups, oil companies now routinely incorporate environmental impact assessments into their corporate strategy. Copyright Springer Science+Business Media B.V. 2006environmental degradation, environmental costs and responsibilities, moral obligation, multinational oil companies, Nigerian oil industry, The Niger Delta,