The COPSE (COincident Probabilistic climate change weather data for a Sustainable built Environment) research project was undertaken between 2008 and 2011. Led by Manchester University, with eventually six academic research partners and the Meteorological Office contributing to the overall programme, the core aim of the project, addressed by the Manchester research team, was to develop robust methodologies for producing weather data les for assessing building designs in future climates, considering the period up to 2080, with particular reference to comfort and energy use. But the scope of the project was much wider; topics studied (and the universities involved) included: • a critical analysis of future projections of solar radiation and its characteristics (Napier) • the impact of future climates on the internal temperatures experienced in typical buildings, particularly examining the proportion of time for which these would exceed conventional comfort temperatures and the additional energy required for mechanical cooling systems (Northumbria); • the interaction between internal temperatures and the external noise environment, now and in the future, since the noise environment in uences the ability of building occupants to achieve comfort conditions by opening windows and increasing ventilation rates (She eld/Liverpool); • the implications for future energy use of the adoption of ‘adaptive comfort’ criteria in the design of buildings, since this approach would reduce demand for mechanical cooling (Bath/Kent); • the Urban Heat Island in the Greater Manchester conurbation, with new modelling tools being developed (Manchester); • the potential change in national demand for energy for space heating and cooling in the building stock (Bath).