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.
Access to an ordinary market is open for to a new entrant , except barrier built by anticompetitive behaviors, punishable by competition authorities, involved ex post.
But there must be a need to organize access, either because there is liberalization of a sector once monopolistic or operators that are too powerful and that State must build this competition for new entrants, or because there are natural monopolies, such as transport networks, which operators must have access to offer their products to buyers by making such transport.
There may still be a requirement to access because yune political to ensure that everyone has access to common property as health, education or environmental healthy, even for free. Thus, arises the idea of a fundamental right of access, which is organizing the regulator ex ante and ex post guard.