Insurgency is one of the oldest and most prevalent forms of warfare. The last fifty years have seen the increase in the numbers and intensity of insurgencies worldwide, particularly in urban insurgencies. Global trends of virtually unconstrained population growth and urbanization (particularly in underdeveloped countries), globalization and the information revolution create conducive environments for urban insurgency. The approach taken in this thesis is to examine three exemplar case studies to determine causation in the outcome of the urban insurgencies, their purposes, differences in technique between rural and urban insurgency, the advantages and disadvantages of the urban insurgent, and whether these advantages were capitalized upon in order to determine the feasibility of urban insurgency in the modern era. The case studies examined were the Battle of Algiers from 1956 to 1957, Uruguay from 1962 to 1972, and Northern Ireland from 1969 to 1974. The conclusion of this work is the feasibility of modern urban insurgency. Urban insurgents will apply modern techlogies to enhance their security, use discriminate targeting, especially in ecomic targeting, and skillfully conduct information operations in exploitation of the media and techlogies for dissemination. Counterinsurgents must win the information war and execute a coherent strategy addressing the underlying cause of insurgency to prevail.