This book contains the papers presented at the Fourth International Conference on Air Pollution, held in Toulouse, France, August 28-30, 1996. The conference brought together scientists working in industry, research organizations, government and academia who are working on monitoring, simulation and management of air pollution problems. Environmental problems due to air pollution are now fully acknowledged by the public and government policy makers as being largely indicative of modern-day living. This book pays special attention to state-of-the-art advances in the experimental and computational measures used to monitor and simulate Air Pollution problems in urban and suburban regions. Only then, can proposed emission control techniques and strategies be evaluated. The book consists of nine sections. These include: Air Pollution and Environmental Modelling; Turbulence Modelling at Small and Meso Scales; Chemical Transformation Modelling; Chemistry of Air Pollution; Fluid Mechanics for Environmental Problems; Aerosols in the Atmosphere; Process Studies; Data Analysis and Observation; and Urban and Suburban Transport Emissions. Each section incorporates up to nine papers.