The present thesis offers a set of theoretical reflections on postmodern and postcolonial territorial restructuring. It is mainly based on fifteen years of scientific research on the demarcation processes at local and provincial levels in African contexts (South Africa, Morocco and Niger) and at intermunicipal level in France. A broad international bibliography on the issues of demarcation and territorial engineering is also used. Chapters deal with specific entries: the arguments on the choice of new provincial capital cities and county-towns; territorial solutions and innovations introduced in borderlands institutional and local government design; the evolution of the optimal territorial pattern in the public policies of spatial planning and devolution. Lastly some laws and trends arising from this work are applies to territorial restructuring beyond local and national political clouts.