This project is a study of Kenya's "war on terror," examining how security practices and counterterrorism are affecting urban space and state power. In recent years Kenya has experienced a number of terrorist attacks that have profoundly impacted the country, placing security at the center of national politics and transforming the very institutions of state security. Through historic and ethnographic analysis of the effects of the war on terror on urban spaces, state practices and institutions, this project studies the broader security-led transformation of Kenyan society. Using archival research, participant observation, and in-depth interviews, I ask: how has counterterrorism been institutionalized in Kenya since the US Embassy bombings in 1998? How have practices of counterterrorism affected the relationship between the Kenyan postcolonial state and its subjects? And in what ways is the implementation of new security practices impacting urban spaces and social relations in Nairobi? The project is structured around three principle avenues of inquiry: (1) historical research on the evolution of Kenya's responses to terrorism since 1998; (2) the legal and institutional reforms of the Kenyan security sector; and (3) the impacts of security practices and counterterrorism policing in the Nairobi neighborhood of Eastleigh. In studying these three important facets of Kenya's war on terror together, this research will offer unique and important insights into the contemporary security-led social transformations in Kenya.