 The Lisbon Charter fills a gap in the global landscape. We add reference documents on the respective walls of stakeholders in water supply and sanitation services. But none of them explored the specific wall of regulatory authorities. Those that apply and enforce standards, criteria, regulations that have been decided, either legally or contractually. So this is new. It is a new document that will be reference documents for all the people in the water sector. The role of IWA as a global association of water professionals is to take advantage of the experience of its many members to guide policies and actions on water and sanitation services. We have to respect the diversity of institutional arrangements. So hopefully we have written something that is useful to all stakeholders in all countries without creating problems to existing frameworks. We believe that as described in this paper, regulation is a function that will be better understood and if better understood it will be better implemented. The Lisbon Charter describes the walls of governments, the walls of service providers and the walls and responsibilities of users. I think the impact will be in the mindset of people. They will better understand the respective walls of different stakeholders in the value chain of water services delivery with two main impacts. One is on the wall of regulators, those that contribute to regulation. But there is also another impact with the description with more details of the walls of the other stakeholders. In particular, the Charter insists on the fact that water users have a responsibility in securing a satisfactory work of the whole value chain.