The societies of the cities of southern Germany were not afraid of innovation at the end of the Middle Ages: over a century (end of the 13th-end of the 14th century), many of them created political regimes integrating social groups, until then excluded from any participation, on a common principle declined according to local situations: the urban council is now made up almost everywhere of delegations of trades (Zünfte) . City dwellers are not satisfied with this first innovation. In many cases, they proceed with great care in putting these provisions in writing: it is these constitutional charters that are at the center of this book. The passage to writing is never obvious; the difficulties encountered by their authors bear witness to the importance of this writing for the companies which produced it. Who are their authors, how did they work? They who were undoubtedly not in contact with the scholarly theory of their time did not leave a theoretical text to shed light on their approach, but these charters make it possible to identify the main lines of their political thought. new institutional device shows it: it is not only an administrative act, but a real political and social program. These charters are the product of periods of unrest, with or more often without violence, to put an end to the political exclusivity of the traditional elites, while ensuring a long-term political balance. To avoid both a return to oligarchic power and destabilization by the popular masses, they have choices to make. Who appoints the representatives of the trades? What weight do the different professions have? What political weight do the traditional elites retain?