40 years after the curtailment of the Basil Spence scheme for Edinburgh University’s city centre campus, a substantial new building is under construction for the largest site that was cleared for development in the 1960s. As the major component of the University’s new masterplan for the George Square/Bristo Square area, it replaces a windswept car park with a rich mix of buildings, courtyards and reinstated streetlines. The new development totals approximately 25,000 square metres and there are three principal users – the School of Informatics, the College of Humanities and Social Science and University Student Support Services. In broad terms, Informatics occupies one building with the remaining users in another, but the scheme also includes street level shops, a cafe and a gallery. Each of these two primary volumes is planned round an atrium, facing each other across a shared courtyard, but their form allows them to overlap on the street edges and undulate in height from three floors to eight. From the inside, the buildings are rational and simple; from the outside they appear far more complex and responsive to their surroundings. Externally, the elevations play on the distinction between the stone-faced streets of Edinburgh and the need for more light-reflective surfaces to the courtyard. Different types of stone cladding and contrasting ratios of solid to void are used to highlight the hierarchy implied by the different facades, Charles Street being the major thoroughfare with the greatest need for animation and Potterrow being more regular. A similar pattern of storeyheight panels is used in the courtyard spaces, but with quartz-aggregate white concrete providing a tone and atmosphere more suited to external spaces in a northern climate. A public pedestrian route passes through the courtyard on its way from Bristo Square to Potterrow, echoing the historic alignment of Bristo Street. The academic space is relatively uniform and, unlike much of the University’s estate, readily adaptable to potential future uses. Most of the accommodation is cellular, so the floorplates have been laid out to ensure that circulation routes engage with a variety of viewing points, open-plan break out spaces and double-height volumes. Construction reflects the simplicity of the plan, with a low energy strategy based on exposed concrete slabs and air supplied from the floor supplemented by opening windows. The first phase of the building started on site in autumn 2005.