Water, the lifeblood of humanity and ecosystems, is a finite and invaluable resource central to survival and sustainable development. Brazil, endowed with 12% of the planet’s freshwater and housing major aquifers and river basins, faces a paradoxical crisis of diminishing surface water amidst abundant reserves. Brazilian law, underpinned by the 1988 Constitution and Law n. 9.433/97, recognizes water as a public asset with economic value, prioritizing its use for human consumption and animal sustenance in times of scarcity. The National Water Resources Policy establishes guidelines for integrated and sustainable water management, emphasizing public participation and decentralized governance. Watershed Committees and agencies coordinate this framework, ensuring balanced and equitable resource allocation. Granting water use rights involves federal and state collaboration, with ANA (National Water Agency) overseeing federal waters. This process, separate from environmental licensing, mandates rigorous oversight to prevent overexploitation and ecological harm. The policy also introduces economic instruments, charging for water use to foster conservation and support management programs. Notable judicial rulings affirm public ownership and prioritize water access for essential uses.