This chapter explores the intelligence mission in the US, considers the evolution of congressional and executive intelligence oversight mechanisms, including the legal bases of outsourcing intelligence from the Cold War to 9/11. For the outsourcing of intelligence before 9/11, both legislative and executive principals produced legal rules, policy letters and directives to regulate intelligence contracting and prevent the delegation of contractors to inherently governmental functions. However, there were significant loopholes in these rules which hampered their implementation. In addition, information asymmetry was evident for Congress due to the lack of information about the contracting inventories of the IC. The brief history of intelligence oversight in the US from the Cold War has demonstrated that executive principals could exploit and mismanage the secret capabilities of the IC to achieve their hidden agendas. In the 1970s, Congress responded to the mismanagement of the IC and to intelligence scandals by establishing new rules and entities, particularly the SSCI and the HPSCI. Despite these landmark evolutions, new congressional control mechanisms could not prevent the subsequent Iran-Contra scandal. Furthermore, under the Reagan administration, congressional intelligence panels began to experience turf wars when the executive policies clashed with the policies of other groups on Capitol Hill. Eventually, regarding congressional oversight, the new monitoring rules and entities were not adequate to monitor the activities of the IC before 9/11. During the Cold War, the IC hired contractors to increase its technological capacity against the Soviets. From military satellite projects to communication technologies, contractors supported intelligence agencies, but because of the narrow intelligence focus on the USSR, intelligence tasks were dominated by federal employees. By the end of Cold War, this trend began to evolve in favour of private actors and because of new operational requirements in several parts of the world, contractors were delegated to carry out intelligence tasks to fill the expertise gap. The executive principal’s policies for the downsizing of the federal workforce, including the IC, increased the need for the skills of private actors. In the 1990s, the US suffered several terrorist attacks around the world but these attacks did not stimulate US decision-makers to transform the IC to address these new security threats.