Denying terrorists sanctuary has become a pillar of U.S. defense strategy since the September 11, 2001 (9/11) attacks. Violent extremist organizations in North Africa, such as the group al-Qaeda in the Islamic Maghreb (AQIM), have used remote and sparsely populated areas in the Sahara for protection from security forces to conduct a range of terrorist activities, such as training, planning, and logistics.1 Despite the time elapsed since the 9/11 attacks, and the resources dedicated to denying sanctuary globally, the concept of sanctuary remains largely unexplored and poorly understood. This monograph proposes a functional understanding of sanctuary and offers fresh ideas to deny it using a detailed case study of the most notorious of these North African terrorists, Mokhtar Belmokhtar, from his arrival in Mali in the late 1990s, until the French intervention in early 2013. Contents: On Sanctuary Terrain: Geographic and Human Characteristics of Saharan Sanctuary Sanctuary Seekers in the Sahara Denial of Sanctuary: Ends, Ways, and Means