Reclaimed wastewater and desalinized brackish or seawater are the two main nonconventional resources developed by the end of the last century in the Mediterranean. Both are intended to solve structural or point problems of water scarcity. Nevertheless, the reclamation and desalination technologies are to be fully developed, although promising possibilities are nowadays in use. Rules and regulations are the main concern for reclamation, since health risks are associated to such practice, while costs are the main limitation for desalination. In any case, decision support systems and other theoretical tools, like Life Cycle Analysis or LCA, will help the stakeholders to decide and fully understand the problems and benefits related to non-conventional water resources.