Odour dispersion modelling was carried out for a proposed residential development at a site adjacent to an existing Sewage Treatment Works. Emissions information was obtained from the operator of the Sewage Treatment Works, which was used in the model to predict existing odour concentrations across the development site. By comparing the model results with a benchmark level, advice could be provided on the areas of the site considered suitable for residential uses. As a result of the modelling, a stand-off distance of 60m was proposed from the boundary of the Sewage Treatment Works. The development subsequently received planning permission.