Abreu, SergioLima, MaíraSantos, Ana SílviaAmaral, Leonor2026-03-182026-03-182025-121366-7017PURE: 150622669PURE UUID: 6cbadfa1-2434-4dbc-a8b3-54e91a9429e6Scopus: 105026880957ORCID: /0000-0003-1125-1764/work/208933107http://hdl.handle.net/10362/201586Publisher Copyright: © 2025 The Authors.Water reuse has been presented around the world as an efficient alternative to the water crisis. In Brazil, this issue has made little progress, as there is a lack of regulation, which represents a major obstacle to reversing this trend. It is necessary to guarantee legal security, the protection of public health and environmental sustainability, promoting a robust and efficient regulatory framework. The USA, Australia and Portugal can serve as models, as they present decision-making structures or general characteristics with some similarities. The methodology builds a line of understanding of the basic elements for proposing a regulatory framework. Step 1 discusses the various legal instruments to be used for regulation. Step 2 presents the experiences of the 3 model countries in the study. Step 3 shows the path already taken in Brazil. Step 4 is the proposal for the regulatory framework for the practice of water reuse in Brazil. Each country that served as a study model presents lessons learned that were incorporated into the structuring of the regulatory framework proposed by this article.16585686engGuidelinesInternational experiencesLegal instrumentsQuality standardsRegulatory frameworkWater reuseGeography, Planning and DevelopmentWater Science and TechnologyManagement, Monitoring, Policy and LawSDG 3 - Good Health and Well-beingjournal article10.2166/wp.2025.245https://www.scopus.com/pages/publications/105026880957