One of the features of compact city is high density and more vertically-used of floorspaces. A multi-unit retail property is the agglomeration of retailers and service providers seeking maximum profit in an architecturally unified building or buildings. Owing to its consumer-oriented nature, the smoothness of pedestrian flows and the efficiency of space allocation are the major concerns for developers and operators. Thus the design of the shopper's circulation needs to consider product varieties, the purposes and behaviours of incoming consumers, and other operational issues. Normally, even with elevators and escalators, vertically movements for shoppers are advised to be avoided. This is because the higher the floor levels the less the motivation; and the higher the searching costs for shoppers. Therefore, the maximum number of floor levels in 148 UK regional shopping centres in 2002 is only 4 levels. However, it is difficult to prevent vertical use of retail buildings in precious central urban areas. In the existing 70 large-scale (over 300,000 sq ft.) shopping centres and department stores, these buildings are with 10 floor levels in average and two of the department stores even with 19 levels. With the spatial data generated from GIS software, this paper aims to reveal the efficiency concerns of the usage of floorspace. And one of the reasons for departmentalizing of retail categories in these high-rise retail properties is to transform non-purposive shoppers into purposive and guided shoppers, which is an opposition from the dispersion result suggested by Carter and Haloupek (2002). The higher and more complex the building is, the more purposive and logical of product variety is needed for customer searching. Hence, retail concentration is a necessity in these properties.