The phenomenon of urban violence and the resulting sense of insecurity are at the very heart of contemporary urban dynamics. In order to respond to the growing public demand for security, various public, private, and community measures contribute to the new urban policies of large cities. This new configuration that comprises security enforcement operates as a "meta-game", in which numerous global economic and civil society actors, such as private security companies and neighborhood communities, are called upon to participate. With regard to security, the principle of governance implies a loss of the State's monopoly of legitimate violence. We have therefore evolved from a regulatory mode, based on disciplinary institutions, to the political inclusion of actors, concepts and means of providing security that jeopardize governability: we no longer know who governs who and the physical and social urban landscapes have been modified. By focusing on urban development practices that aim to physically resolve insecurity problems and perceptions in cities, our objective is to analyze the extent to which the governance system of security has led to a radical and significant transformation of cities and the practices of its inhabitants, notably through the reinforcement of spatial and social fragmentations. Unequal participation is a reflection of unequal access to public space, and vice versa. The city is leaning towards a global and hegemonic model of public space, where the routine enforcement of order is imperative through the use of appropriate planning policies. We question the degree of publicity of public spaces and the democratic management of urban territories. The "generic" city seeks to eliminate or hide anomic behavior. However, violence adapts to specific forms of urban territories, with the form of the city determining their substance. Consequently, violence should be interpreted as a reaction triggered by the way in which society is organized. Instead of reducing urban violence, the use of security planning in urban areas often territorializes it. A geography of violence reflects the geography of security. With the transition from governmentality to governance in the security field, society has also evolved from fragmentation to greater segregation of urban areas. Efforts must be made by public authorities to reconfigure their structures in order to respond, by themselves, to the public demand for security. To avoid the transition from conflict to violence, the anomie in the city must be reconsidered and urban risks resolved within a framework of inter-sectorality.