This book investigates the parliamentary negotiation of executive secrecy. Parliaments depend on information to fulfil their roles as the people's representatives, legislators and overseers of the executive. However, there are examples of executive secrecy across all policy fields. How, then, do parliamentary actors try to reconcile secrecy and the normative demands of an open, democratic society? This volume analyses parliamentary arguments, conflicts and patterns of agreement around this topic in the case of Germany. Based on two case studies – intelligence agencies secrecy and Public Private Partnership secrecy – it argues that substantive justifications of secrecy focusing on necessity are highly contested. By contrast, procedural legitimation of secrecy, namely deciding about it democratically, is crucial. Still, there are inherent limits to the legitimation of executive secrecy. The book therefore underlines the fragility of secrecy's legitimation, and its need for constant actualisation.