This dissertation examines the sensory entanglements of security through an analysis of contemporary art and ethnographic encounters. I argue that the “securitization” of society does not only entail a multiplicity of actors and practices, as Marc Schuilenburg demonstrates, but sensory attunements that bring technologies, bodies, and spaces into security assemblages. The project is in line with recent scholarship on the senses in the social sciences and the humanities, what anthropologist David Howes identifies as the “sensory turn.” In particular, the project resonates with the work of Tim Ingold and Davide Panagia as they argue that the senses are phenomenological, social, and political. I extend this understanding of the senses to the topic of security. To analyze the sensory dimensions of security, I consider a diverse set of materials, including artworks, ethnographic research, news sources, industry trade journals, and official government materials. From this collection of material, I draw out sensory moments and lines of sensation, examining the ways that seeing, hearing, touching, and smelling are at work in security. In this project, “sensing security” holds three meanings: first, I use it to refer to the sensory technologies that increasingly have become a part of contemporary security and how security acts as a sensing mechanism. Second, it refers to the way security conditions the senses, instructing us on how to see, hear, and touch. Security discourse not only outline threats but also teaches us to turn our bodies into security machines in order to identify suspicion and alert authorities: enlisting our eyes, for example, in the counterterrorism campaign “If You See Something, Say Something™.” Finally, by using this phrase I attempt to capture the work I do in the dissertation, as the project explicates, or senses out, the entangled sensory relations of security.