The paper deals with the relationship between labour law and civil (private) law. This relationship is a classic subject of reflection, even in common law systems, for labour lawyers who are searching for their own identity. It is often said that if civil law is the realm of individual autonomy and freedom of contract, then labour law is the realm of mandatory rules. Nevertheless, we have observed since the 1980s, on the one hand, the erosion of the principle of inderogability in the field of labour law and, on the other hand, protection techniques in the field of civil law that mimic those of labour law. Starting from this analysis, the a. discusses the rationale behind the principle of inderogability in labour law and the debate, among Italian scholars and in the international literature, on the enhancement of contractual autonomy in the labour relationship.