This report wants to contribute to the debate that is carried out in the countries of the region on the improvement of the regulatory framework of the sector of potable water and cleaning. The attention is concentrated in how the availability of the information for the economic regulation is guaranteed. The consequences and conditioners of the asymmetry of the information between the regulator and the regulated companies are examined, as well as the procedures that can be used to surpass it. The regulatory practices of the developed countries are examined, mainly those of the United States of North America and the United Kingdom, which are compared with the existing situation in the countries of the region. The study is based on: (i) answers to the survey on the subject, that the Division of Natural Resources and Infrastructure of the Cepal sent to the regulating organisms of the countries; and (ii) the revision of the theoretical and empirical bibliography on the economic regulation. The main conclusion that it is obtained from this work is that the regulatory marks of the countries of the region do not guarantee an adapted access of the regulators to the information that they need for the performance of their functions and that some of the characteristics of their design tend to increase the informative advantage of the regulated companies. In the region, greater attention to the development of theoretical procedures of access to the information has been lent and they have not worked and the experiences of the countries with one long tradition in the benefit of services public by the private sector has been ignored. The priority now is to fortify, to consolidate and to make the operative the procedures of access to the internal information of the regulated companies, specially the regulatory accounting, the control of purchases, and the participation of the consumers.