While there has been an increasing recognition of the health impacts of air pollution assessment of air quality and health impacts is rarely adequately reviewed in planning decisions. Planning decisions are generally based on meeting national annual average air quality targets despite substantial evidence that levels below these are harmful to health and references to population health impacts in the UK National Planning Policy Framework and Environmental Assessment Guidance for planning. This article reviews the current framework and discusses how air quality has been taken into consideration in some recent planning decisions and legal appeals. Problems in assessing air quality in planning decisions and the increasing evidence on the long and short-term impacts of poor air quality are highlighted. The article concludes by arguing that health impacts should be more clearly addressed when considering air quality assessment setting out some potential approaches to how this could be incorporated in the planning process.