AbstractThis article sets the global scene for the regional and local levels elaborated upon by articles later in this special issue by addressing the following research question: What is the impact of a human right to water on the sustainable balance of water uses under the customary international water law principle of equitable and reasonable utilization as codified in the UN Watercourses Convention? In order to answer this question, first, both a human right to water and vital human needs are introduced. Second, the position of a human right to water under the UN Watercourses Convention is reviewed, focusing on vital human needs that require special regard in order to reach equitable and reasonable utilization of freshwater resources. Third, various water uses to be taken into account when aiming for a sustainable balance are considered. Finally, the shift in balance by the coming into existence of a human right to water is concluded upon: It is argued that the impact of the human right to water results in effective priority of water uses for vital human needs in the application of the principle of equitable and reasonable utilization of international watercourses, reinforcing the human right to water beyond borders in return. This article contributes to the legal discourse by linking the general principles of international water law to the human right to water, which are foremost dealt with separately in existing literature, and clarifies the position of this right in the balance of water uses in cases of transboundary water allocation.