This paper reviews research conducted in the past two decades in urban-scale air quality modelling in Australia and New Zealand, with emphasis on prognostic models. With advances in computer technology – especially desktop computers – air pollution dispersion modelling is now a feasible undertaking not only for wellfunded research institutions, but also for air quality consultants. It has been suggested that as prognostic models become more user friendly they will eventually replace Gaussian dispersion models as a tool for urban air quality impact assessment. However, for now, Gaussian models are still widely used. Prognostic dispersion models have been applied to a number of Australian and New Zealand urban regions with relative success. In Australia, the major focus has been in simulating photochemical smog episodes. In contrast, New Zealand studies have mostly dealt with nocturnal dispersion of particulate matter during stagnant weather conditions.