The UNESCO General Conference approved, in October 2009, the establishment of the International Centre for Coastal Ecohydrology (ICCE), under the auspices of the UNESCO, in Portugal. Human pressure on coastal areas has dramatically increased during the last decades and it is expected to continue to increase in the future. Adding to this scenario, climate changes will pose new threats to coastal areas, as expected from sea level rise and the decrease in freshwater discharges from rivers. The ICCE aims to contribute to the dissemination and implementation of the UNESCO-IHP Ecohydrology approach to coastal ecosystems worldwide. In this paper we provide examples of the application of Ecohydrology to the sustainability of the Guadiana Estuary in Southeast of Portugal that are feasibly transferable to other estuaries suffering similar anthropogenic impacts.