Increasing calls for intelligence support and continuing innovations in intelligence technologies combine to create significant challenges for both the executive and legislative branches. This report discusses Intelligence, Surveillance, and Reconnaissance (ISR) systems, which are integral components of both national policymaking and military operations, including counterterrorism operations. ISR systems are costly and complicated, and the relationships among organizations responsible for designing and operating these systems are equally complicated. These factors create numerous oversight issues for Congress, which this report addresses