The Ordinance of Villers-Cotterêts is an extensive piece of reform legislation signed into law by François I of France on August 10, 1539 in the city of Villers-Cotterêts.

Largely the work of chancellor Guillaume Poyet , this legislative edict, in 192 articles, dealt with a number of governmental, judicial and ecclesiastic matters (ordonnance générale en matière de police et de justice).

Articles 110 and 111, the most famous, prescribed the use of French in all judicial acts, notarized contracts and official legislation in order to avoid any linguistic confusion:

Nous voullons et ordonnons qu’ilz soient faictz et escrits si clerement qu’il n’y ait ne puisse avoir aucune ambiguïté ou incertitude, ni lieu à en demander interpretacion.

We wish and command that they be made and written so clearly that there neither be nor be any possibility of there being any ambiguity or uncertainty, nor cause to ask interpretion thereof.

The major goal of these articles was the discontinuation of the use of Latin in official documents (although one continued to find Latin used in church registers in some regions of France for some time to come), but they also had an effect on the use of those other dialects spoken in many regions of France (see Languages of France).

Other articles enforced the recording, by priests, of baptisms (necessary for determining the age of candidates for ecclesiastical office) and burials, and required these acts to be signed by notaries.

Another article prohibited artisanal and trade federations (toute confrérie de gens de métier et artisans) in an attempt to suppress workers' strikes (although mutual-aid groups were unaffected).

Many of these clauses reveal an expanded, unified and centralized state, and the clauses on the use of French mark a major step forward in the linguistic and ideological unification of France at a historic moment of growing national identity.