The article examines the evolution of the Belgian electoral map, from the property qualification to the latest parliamentary elections in June 1999. It stresses the permanences of the regional electoral behaviours and those of their determining factors while placing the advances and breaks in the context of the long-lasting phases of the social and economic development. In spite of a tendential score decrease since 1965, the social-christians keep the most stable geography. So do the French-speaking socialists, whereas on the contrary the Flemish socialist geography has lost its « central » character to become a « peripheral » one since 1981. The liberal geography is the most unsteady and appears more and more focused on the biggest metropolitan employment basin while competing with the social-Christian vote in the « peripheral » areas, especially in Wallonia. The extreme right and the Ecologists share a more « central » geography, which indeed reflects sociologically opposed electorates, both nevertheless determined by post-Fordist stakes.