Access is a key concept in regulation since only a competitive market allows access for all to becom offerers and applicants. This is why regulations and regulators intervene ex ante to force access to natural monopolies, such as transport networks, for the benefit of other operators. Thus, Regulation compensates for market failures by imposing access. In addition to these access imposed for technical reasons, the Politics can still intervene to force for all access to common goods, such as culture, health, education, referring to the Social Contract. The foundation, political, is different.