This chapter reviews the question of effective oversight in democracies regarding transnational operations by intelligence services resulting in important violations of human rights. The Central Intelligence Agency (CIA) was determined to avoid collaboration with any European intelligence service subject to effective democratic oversight. Further, the CIA programme also depended on intelligence services in other states to share personal information in order to identify who the suspects should be. The Venice Commission updated its 2007 report in 2015, providing a new report on the democratic oversight of the security services and the democratic oversight of signals intelligence agencies. Also in 2015, the Council of Europe's Commissioner for Human Rights published an issue paper entitled Democratic and Effective Oversight of National Security Services. The study recognizes that while quite a few Council of Europe states have established some oversight bodies, very few have introduced systems of evaluation of the effectiveness of those bodies in carrying out oversight of the intelligence services.