Polycentric law is a legal structure in which providers of legal systems compete or overlap in a given jurisdiction, as opposed to monopolistic statutory law according to which there is a sole provider of law for each jurisdiction. Devolution of this monopoly occurs by the principle of jurisprudence in which they rule according to higher law. Professor Randy Barnett, who originally wrote about "non-monopolistic" law, later used the phrase "polycentric legal order." He explains the advantages of such a system in his book The Structure of Liberty: Justice and the Rule of Law.