In the present chapter we argue that to try to cope with new technologies with the concept of regulation is problematic from a legal point of view. Lawrence Lessig’s approach of ‘regulation’ as the ‘optimal mix of technology, law, social norms and market mechanisms’ should be complexified, as those modalities have different aims, functions and rationales. In view of a critical discussion of Lessig’s concept of regulation, we introduce Isabelle Stengers’ view of what defines a practice in general and Bruno Latour’s view on what defines the legal practice in particular. Law, science and politics have different constraints and conditions of success, and are embedded in different ‘régimes d’énonciaton’. Any articulation or interweaving of law, technology (code), economy and social norms must be sensitive to their differences and particularities, as they render very difficult the reduction of any of these practices to just another modality of regulation. Law, notably, cannot be shrunk to a legislative-regulatory dimension that does not take seriously what lawyers do when making the law, especially in the lower courts. Regulation is too general a concept to recognise the specificity of legal practice, particularly in its confrontation with new technologies. Moreover regulation is too powerful a concept to allow the novelty of emerging technologies to be taken into account by those who, like legal practitioners, have to deal with it at their own pace and with their own tools and responsibilities.