This book examines the constitutional status of Old Catholicism for the first time in its entirety. The Old Catholics occupy a unique position because, due to their history and the resulting self-understanding, they largely take advantage of the special state offerings for religious communities, particularly the opportunities associated with corporate status. This distinguishes them from most small religious communities. Therefore, Old Catholicism allows for an insight into the resilience of the constitutional system and ultimately provides information about its legitimacy in light of the liberal stance of the Basic Law.