Summary A simple regression model is developed for the identification of long‐term trends in structural unemployment within regional labour markets. The model is applied to monthly unemployment rates recorded in 73 employment districts in Australia from July 1955 to December 1970. It is shown that, over the study period, the regional system was characterized by increasing spatial imbalance in the incidence of structural unemployment. A distinct rural/urban dichotomy is apparent with rural areas experiencing increases in structural unemployment and the major metropolitan areas (with the exception of Adelaide) significant decreases. Evidence is presented relating the trends identified to the vulnerability of regional economies to structural change and to interregional employment shifts taking place within the regional system.