This article assesses the impact of reunification on the Bundestag from a historical institutionalist perspective. Accordingly, it focuses on procedural development and parties’ behaviour. More specifically, it analyses parties’ control of the legislative agenda and their willingness to obstruct this agenda. Prior to reunification, the Bundestag emerged as a working legislature with decentralised agenda control. Even though the Bundestag was vulnerable to obstruction, especially by questioning the quorum, obstructive behaviour virtually ceased after 1951. After reunification, the Bundestag’s vulnerability was increased when a plenary ‘core time’ was introduced in 1995. However, all parties, including the one most directly related to reunification, the Left Party, continued to abstain from exploiting procedural loopholes. Only the AfD as the other post-1990 newcomer (albeit less directly related to reunification) did so by questioning the quorum to an unprecedented extent after it entered the Bundestag in 2017. So far, this systematic obstruction has only led to a path-dependent procedural reform. If, however, the AfD continues with this behaviour, it can be regarded as a threat to legislative democracy at least indirectly related to German reunification.