We use entropy indices to describe sectoral location patterns across Western European regions over the 1975?2000 period. Entropy measures are decomposable, and they lend themselves to statistical inference via associated bootstrap tests. We find that the geographic concentration of aggregate employment, as well as of most market services, has not changed statistically significantly over our sample period. Manufacturing, however, has become significantly more concentrated relative to the distribution of aggregate employment (increased brelative concentrationQ), while becoming significantly less concentrated relative to physical space (decreased btopographic concentrationQ). The contribution of manufacturing to the topographic concentration of aggregate employment has fallen from 26% to 13% over our sample period. D 2004 Elsevier B.V. All rights reserved.