This paper assesses the forces that drive the development of clean fuel technology. The focus is principally on policies and regulatory measures affecting combustion emissions. However, the paper also covers more briefly discharges to other media and the control of greenhouse gas emissions. The broader forces shaping UK policy are assessed. It is concluded that international obligations continue to be an important driver, though the United Kingdom is influencing international developments to a greater extent than was the case 10 years ago. The paper covers both European Union initiatives, such as integrated pollution prevention and control and a revised large combustion plants Directive, and wider international agreements on long-range pollution and climate change. The paper also examines how the UK Integrated Pollution Control regime is being implemented and considers emerging UK policy initiatives, including a draft sulphur strategy and local air quality management. The paper ends with a review of longer term trends, including the possible adoption of market-based instruments and a more aggressive climate policy.