Intelligence oversight, defined as a special control of intelligence services by national parliaments, is a fairly new function in the development of modern governance as is also research into that function. It reaches back only to the 1970s in the United States and to the 1990s in Britain. To be sure, there are some exceptions. The Netherlands established a specific parliamentary control in 1952; Germany (then West Germany) did so in 1956. France, one of Europe's oldest parliamentary democracies, passed its first extensive legislation in 2007.

Parliaments, however, are not alone in checking on what intelligence services do. Primary responsibility for their proper functioning lies with the executive. Governments are politically responsible to parliaments and to the public for what intelligence does or fails to do. Yet, they face a difficult-to-resolve dilemma. Due to extremely tight security requirements, only a small number of government ministers and officials are in a position to monitor continuously and systematically the potentially most dangerous and most controversial intelligence operations. Because these are the same people who also give the orders, they are understandably reluctant to burrow deeply into intelligence failures of one sort or another. As a result, the most powerful oversight instrument is also the most unlikely to do the job rigorously. Typically, it takes an intelligence “scandal”, revealed by the press to the public, to get parliaments and executive overseers to act. In some cases, the judiciary becomes involved in pinpointing intelligence failure and forcing the executive to make needed changes.