Today, urban air quality in Canada is subject to regular monitoring as the human health impacts of exposure to various contaminants are better understood. The sources of air contaminants and the interactions among them clearly affect local air quality, as do factors such as geographic location (coastal versus interior), seasonality and weather conditions, and the extent of trans-boundary pollution. In both Canada and the United States, national and provincial/state regulations exist to manage air quality and set standards for emissions. In British Columbia, Metro Vancouver (formerly the Greater Vancouver Regional District) is in a unique position within Canada because it has delegated authority from the provincial government to regulate air quality in the Lower Mainland. Recently, Metro Vancouver released the long-awaited summary of its 2005 air emissions inventory. This issue of the Business Council’s Environment Bulletin reviews the results of the inventory, examines the projections developed by Metro Vancouver staff, and considers some implications for regional and provincial policy on air quality going forward.