This article tries to outline possible research topics in the field of comparative 20th century legal history between Europe and Latin-America. It seeks to examine changes both in Labour and Property law as core areas where social conceptions began to influence »liberal« private law. Focussing on an example from Mexican law in the aftermath of the revolution which took place in the first decades of the 20th century, it is argued that new conceptions in both fields were discussed using similar conceptual patterns in Europe and Latin-America. In the reaction of the jurists from both continents to the challenges of the new century lies a possibility for fruitful comparison. Conducting research in such a framework can also produce comparative results on the interplay between constitutional law and private law – especially when the focus lies on Germany and Mexico, where new constitutions at the beginning of the new century did evoke reactions in the discourses about private law. With regard to methodology it has to be observed that such research has to go far beyond the traditional pattern of »reception« of legal concepts from Europe in Latin-America, and to highlight more complex ways of transition of legal forms between the two continents.