The efficient design of parking lots is an important element in the development of the transport infrastructure. The design process often adopted is based on broad measures of parking demand, design manuals outlining the minimum size of the components and the experience of the designer. This process may not result in the best design. It is of particular concern that this process does not provide any quantitative information on the ‘level of service’ resulting from the choice of a parking layout. Models of parking systems provide this assistance. Existing models provide information on the utilization of the parking system, its capacity, the best distribution of parking space use and the delay experienced by parkers. Recent improvements in these models have been aided by rapid developments in computer and graphics technology. This paper reviews developments in models of parking lots.