Divided cities (Belfast, Beirut, Nicosia, Jerusalem, Mostar, etc.) bear witness to more than the punctually unbearable aspect of inter-community conflict; they also represent the regrettable result of a wider failure of local governments, of the intolerance caused by sectarian entrepreneurs, or in short, the failure of the urban contract. Because of its high cost in both monetary and human terms, physical partition should be avoided, even though the mechanisms of such partition suggest that prevention is to some degree possible.