Résumé : We study the link between economic structure and growth in the 43 Belgian ‘arrondissements’ between 1991 and 1997. We find empirical evidence that local economic structure has a significant impact on the local growth of the service sector as a whole. Sectoral specialization and competition would affect negatively local growth in this sector while we find strong evidence of a positive effect of sectoral diversity. The size of the local market would not play any role on growth but the average local income does so. Our results are consistent with those found by COMBES (2000) for local growth in France.