English
The notion of legal regulation appears vague and polysemous. It may convey three different types of meanings: regulation might be understood as a substantial attribute of law itself, or as the typical feature of Welfare State law, or as the indicator of the transformations currently undergone by legal systems. After having pointed out how these various meanings may be combined, the author shows that legal regulation is now produced by a set of different actors, standing in different legal spheres. Such a dispersal cannot but affect the regulatory function of law, the proliferation of rules tending to deprive law of some of its efficiency.