This publication demonstrates the continuing health and societal impacts of poor housing in Wales. Proportionately, there is considerably more poor housing in Wales than in England, with dangerous stairs and steps, and cold and damp homes being key problems. It is estimated that works targeted on reducing the worst hazards would have a benefit to the National Health Service of some GBP67 million per year. This figure doubles if the definition of poor housing is widened to include all homes with a SAP (energy efficiency rating) of 40 or less and basic heating and insulation improvements are targeted towards these homes. In addition to the direct costs, poor housing also results in broader economic consequences for society in Wales which can be calculated at a further GBP100 million per annum. The research was commissioned by Shelter Cymru and BRE Trust.