This chapter examines the nature of the obligation of states to progressively realize the human rights to water and sanitation, aiming at informing public policies on the operationalization of that obligation. Even with more than one decade since the General Assembly explicitly recognized water and sanitation as a human right, it is often not clear how to unpack the generality of the obligation of progressive realization of human rights, particularly in the era of the 2030 Agenda. Both the SDGs and the progressive realization obligation have been criticized for being aspirational goals, the former because of the significant margins of discretion given to each state to set their own national targets and the latter because it is viewed as vague, having no defined time frame or pace of implementation and therefore not imposing a clear positive obligation on states (Porter, 2015).