Family law in Europe is facing new challenges.   Growing mobility and the increasing internationality of family relations create problems due to the profound differences in national family laws. The Franco-German optional mat- rimonial property regime marks an important initial step in a unification process, since it creates identical family law in two European countries for the first time. However its scope is limited and many uncertainties remain. In contrast, a wholly new model – the European marriage – could allow couples with cross-border elements to avoid such imponderables by choosing an all-encompassing unified legal framework at the moment of celebrating mar- riage, including provisions concerning marriage and its general effects, marital property, divorce and post-marital maintenance. The optional European marriage could contribute to predictability of legal consequences for transna- tional couples whilst preserving diversity in European family law.