Increased vehicle emission in Colombo is one of the most important environmental issues that has drawn the attention of policymakers, administrators, and environmentalists in the recent past. Various studies undertaken by regulatory agencies and researchers clearly indicate that inefficient combustion of petroleum in motor vehicles is the primary cause of growing air pollution in Colombo. Lack of information on economic and environmental costs of vehicle emission and its mitigation and prevention have inhibited public response and enforcement, and impeded the implementation of existing laws, and the development of further regulations. Policy-oriented research in these areas may contribute to a better understanding of the problem and the introduction of effective control measures.