Luisa Becker-Ritterspach explores the question of why large projects, such as the expansion of Frankfurt am Main Airport and the construction of Berlin Brandenburg Airport, suffer from such long planning times. The author views the construction of large projects as a dual implementation process, as not only must the actual building be constructed and completed, but also every single formal and informal procedure must be implemented. Seeking the reasons for long planning times solely in the multitude of actors and their specific interests, as implementation research attempts to do, is no longer sufficient. The case studies were examined using the governance approach, actor-oriented institutionalism, and organizational theory, which identify the causes within the institutions as well.