Census data from Queensland were used to test whether or not the relationships between population and retail trade patterns derived from central place theory were applicable at the local authority level. Larger local authorities achieve higher per capita retail sales than less populous places. Proximity to larger centres reduces per capita sales. Population growth allows a local authority to capture a higher proportion of spending locally, while decline encourages and even forces people to shop elsewhere. There is a general tendency toward fewer retail firms, presumably due to technological changes in retailing, but the rate of loss is related to population change. Only places with moderate population growth show increases in firm numbers. Changes in retail sales per firm are also directly related to population change.