Microregional fragmentation in a Swedish county**This article is based on a research project carried out at CERUM (Centre for Regional Science, Umeå University, Sweden). The project was initiated by Professor Ulf Wiberg (Department of Social and Economic Geography, Umeå University, Sweden) and Lars Olof Persson (Nordic Centre for Spatial Development, Stockholm, Sweden) and was partly financed by the County Council of Västerbotten. The author wishes to thank the editor and three anonymous referees for valuable comments

This study of the county of Västerbotten in northern Sweden reveals significant differences in socio†economic conditions between populations living in different residential environments. A cluster analysis was performed in order to classify the nearly 500 microregions into a manageable number of groups with distinctive profiles. A seven†cluster solution contains groups ranging from remote and sparsely populated areas with poor socio†economic conditions and a large proportion of elderly to the most prosperous residential environments within the major centers. Besides high disposable incomes, the relatively wealthy areas also show high educational levels and better†than†average health status. In this way the county could be broken down into a mosaic of local housing environments with very different prerequisites for consumption and economic development. Increasingly, we find socio†economic marginality problems even within densely populated regions. The complex and dispersed pattern of disadvantaged and underprivileged residential areas all over Västerbotten indicates the difficulty in treating counties and municipalities as homogeneous regions. Our findings may have major implications for regional planning and regional policy.