THESSALONIKI – The governance and exploitation of water resources in a cross-border water catchment area or river basin is frequently a point of friction between neighboring countries and has already led to the appearance of a new term: «hydro-diplomacy.» A typical example, referred to recently by Associate Professor I. Mylopoulos of Thessaloniki University on the occasion of World Water Day, was Turkey’s dispute with Syria. The former state closed its dams on the Euphrates in order to pressure the latter to hand over or drive out Kurdish rebel leader Abdullah Ocalan. There are likely to be more of these instances in the future as control over water resources in particular areas becomes a bargaining tool, according to the professor. In Macedonia and Thrace, governance of cross-border rivers, which consitute 25 percent of the country’s entire annual water capacity, to a great extent affects and determines agricultural, urban, industrial and tourism development as well as the protection of ecosystems and the natural environment of northern Greece. Of these four rivers (the Axios, Strymon, Nestos and Evros), only the Nestos’s water is governed by an interstate agreement which, however, has come up against obstacles, as evidenced by the recent movement of large quantities of Bulgarian garbage downstream to areas around Drama. With regard to the Axios, there are worrying indications that all the urban and industrial waste from the Former Yugoslav Republic of Yugoslavia is flowing downstream, threatening to contaminate the broader catchment area in the prefectures of Kilkis and Thessaloniki, the river delta and the Thermaic Gulf that it flows into.