The reduction of carbon dioxide (CO2) and equivalent emissions in Europe and other developed countries is now part of the mainstream political and social agenda, with particular focus on the performance of the built environment. Traditional and historic buildings are under significant pressure to reduce the carbon emissions associated with their operation, and Historic Scotland is taking a lead in the provision of guidance and advice for traditionally built structures of all type in Scotland. Following the established principles of traditional construction, its programme of research has looked at the thermal performance of the traditional building envelope and how it can be improved by sensitive and appropriate intervention; key processes and initial findings are presented and the savings achieved in certain site projects. Other related factors such as passive benefits and sustainability issues are presented together with an outline of the future research programme. PSUBKY=energy;efficiency;building;traditional;refurbish