The issue of regulation of natural public service monopolies has always been the subject of an ample and complex academic debate since the beginning of economic science. Moreover, the public utilities of potable water, electricity and telephony represent a basic need of the population in any country in the modern world, given their notable importance to the level and quality of life of people. For these reasons, the regulation and administration of companies that provide those services have also been the subject of great political and social debate. This study is a theoretical and empirical synthesis of the new focuses of the regulation of natural monopolies, which are among the most recent advances in modern economic theory and have been applied in the 80’s in Chile. In this regard, the Chilean case represents an exemplary and unique situation in the world. In fact, other countries have attempted these modernizations without achieving the same success as Chile thus far to date. Modernization of the regulation of these public utilities in our country represents a milestone in connection with rate-setting, the concession regime, control and oversight, subsidies and privatization.