The frontier, the boundary and isolation. The case of small insular economies This paper deals with isolation as a bad development factor for little insular regions. From a sample data dealing with some European regions, the regional GDP is explained by two variables which are linked with the external economic potential of the corresponding regions : population and distance from the European centre of economic gravity. The majority of islands are shown to have negative residues. Isolation (which we have to distinguish from the concept of peripherality) is thought to be responsible for this result. Isolation is not only a territorial discontinuity which hinders the island-continent relations ("external" isolation), it also refers to the sta...