Since Goethe's comment on the cannonade of Valmy, "From here and today a new epoch of world history begins," the term "historical turning point" has become one of the standard metaphors in historiography. It enjoys particular popularity in constitutional history. Because not only does every new constitutional document claim to herald a new era, but even any change to existing constitutions that goes beyond mere cosmetic adjustments seems to signal a new time, these turning points appear to be particularly densely sown in this field. At its annual conference in 1991, the Association for Constitutional History examined whether this is indeed the case. It was less concerned with where the turning points in German constitutional history can be identified. The focus was on whether the processes of the emergence and decline of systems of governance and constitutional systems can be adequately represented.