As sustainability cannot be imposed in a dictatorial manner but only learnt, society requires methods to make such teaming effective at the societal level. Therefore, under such perspective, sustainability could be viewed as a "reflexive teaming process". This is exactly what this paper intends to deliver, especially to the scientific community striving to alleviate the freshwater scarcity crisis. However, in order to fully embrace the concept of sustainable water management, one should look beyond the limits of technology. This work, therefore, freely overshoots the scope of desalination technology as such. The direct per capita availability of freshwater resources decreases as the world population continues its growth. This fact threatens not only future economic growth expectations but also more importantly the well being and subsequently the survival of humanity as a whole. In the present debate, the Canary Island of Lanzarote (Spain) and the City of Laayoune (Moroccan Sahara) are taken as case studies. The North-South approach is used to raise certain questions on the significance of scarcity. Indeed, the issue of "water for tourists" might seem far removed from water scarcities for poor people in the South. If we assume a technological trajectory or decreased monetary costs, decreased energy costs per cubic metre, and moreover increased share of renewable energies in desalination (a kind of win-win-win scenario), does this mean that water for urban use of poor people in the world will cease to be a problem? Will not the energy costs remain too high, anyway? Here, an approach from the "basic needs" scenario (free lifeline, in South Africa) is relevant.