A series of preliminary wind-tunnel tests have recently been carried out on a model of a proposed Liverpool Civic and Social Centre (for which the architect is Colin St J . Wilson). These tests were primarily concerned with investigating one aspect of the wind pattern around the building— how it affects the pedestrian. The value of initial, or exploratory, testing has been that the opportunity could be taken to use a short (2- or 3-day) availability of a wind tunnel, in this case offered to us by courtesy of the University Engineering Laboratories at Cambridge, to place in it an existing model of the scheme. From this has been obtained a guide to the types of detailed testing that will be necessary as the design progresses. The form of the building complex in the study model (figures 1 and 2) can be separated out vertically into three main elements: (i) Five upper floors of offices, which house 4500 members of the Corporation Staff and, in the centre block, connect to a public reception hall handling up to 8000 visitors on a normal day. (ii) At mid-level a pedestrian route system across the site in the form of a covered arcade with attached commercial accommodation. (iii) In the four to six lower levels of the podium a social and public realm with sports and swimming centres, restaurants, multi-purpose hall and adult education facilities. The overall dimension of the pinwheel forming the upper office levels is 244 m (800 ft) from east to west and the centre hall section is 73 m (240 ft) square. The first testing of environmental conditions has been carried out on a 1/500 scale wood and polystyrene model which allows for the Civic Centre together with its immediate surrounding area of Liverpool to be assembled on a baseboard 1.3 m square