Over the past twenty-five years International Water Law has undergone a profound transformation, real paradigm shifts. The “old” paradigm was based on purely intergovernmental law, minimalist in its obligations and contractual in contents. Its regulatory scope was equally limited. The legal order is hard to distinguish from the rights and obligations negotiated. The only principle that may be inferred therefrom is that of equitable utilisation, barely constrained by the vague notion that efforts should be made not to harm the neighbouring State. The mere conciliation of interests is pursued. Contractual in nature, compliance to this Law leaves much to be desired. Since the 1990s, however, this normative panorama has been experiencing fundamental changes. The first sign was a profusion of international conventions. Amongst them, the following ones deserve particular mention, because they represent innovation and indicate new trends: on a global scale, the UN Convention; at the regional level, the Water Convention, adopted under the auspices of the UN Economic Commission for Europe; and at sub-regional level, the 1998 Luso-Spanish Convention. They set out new substantive, procedural, logistical, institutional legal solutions concerning international water management, with the aspiration to efficiently respond to the global water crisis, a new world, as well as new normative expectations. The other sign is a recrudescence in litigation which are, however, submitted to international justice. Five main cardinal options underpin the new Law, which is driven by a number of values and goals. The first of these options is that water management be holistic. It is thereby hoped that the reality of Nature and problems be better apprehended so as to ensure efficiency. The second one is the one of the environmental protection of waters and associated ecosystems, as well as the prevention of impacts and the pursuance of water quality. Henceforth, any new water development project must prove to be sustainable. The third choice is one of pursuing the democratisation, inclusiveness and humanisation of relevant legal relations. For that, other States, international organisations, NGO, individuals are integrated, in an effort to ensure a better water governance and of obtaining better decisions. This new direction takes on the juridical form of granting procedural rights of access to information, public participation in decision-making processes and access to justice. A human right to water and sanitation is also recognised. The fourth option may have just been emerging, thus implying more problems and queries than certainties. It involves an attempt at capturing the economic value of water, both as a good and a service. The main question that it poses is whether the disciplines of international economic law may and should be applied to the specificities of this good. Last but not least, there is also a resolute choice for a strong legal order, more complex but also more robust and consistent. By means of using the general principles discernible in international water law, a greater integration is pursued with other legal areas and complex legal orders, thus furthering the international rule of law in the area of water and water governance. The progress made is not, however, deprived of uncertainties, hesitations and even resistance, as is proper of paradigm shifts of such magnitude and ambition. With climate change, the water legal order is reminded of the need to constantly reinvent itself.