This article argues that, despite an ongoing global revolution in urban demography, most Western military research into urbanization is narrowly focused and remains disengaged from the interdisciplinary expertise of urban studies. Because so many cities are sui generis in terms of their governance, architectural design and demographic composition, the art of war must seek closer interaction with the science of cities. In the coming years, in order to control armed violence and reduce casualties across an urbanizing world, military analysts must seek greater cooperation with urban specialists. The common aim must be to develop an urbanoriented strand of strategic studies that is firmly based on a sophisticated understanding of the ecology of cities. Such a cooperative approach will assist in the development of military methods of operating in cities using appropriate rules of engagement that embrace international humanitarian law.