The Convention on the Non-Navigational Uses of International Watercourses (IWC) was adopted by the United Nations General Assembly in 1997.  The Convention applies to uses of international watercourses andof their waters for purposes other than navigation and to measures of protection, preservation and management related to the uses of those watercourses and their waters. If a use affects navigation or if navigation affects a use, the convention may apply. It should however be kept in mind that ratification of this convention goes slow and that at the end of 2006 it had not yet entered into force, because there was not a sufficient number of ratifications.
- Watercourse: "a system of surface waters and groundwaters constituting by virtue of their physical relationship a unitary whole and normally flowing into a common terminus"
- International watercourse: "a watercourse, parts of which are situated in different States"
- Watercourse State: "a State Party to the present Convention in whose territory part of an international watercourse is situated, or a Party that is a regional economic integration organization, in the territory of one or more of whose Member States part of an international watercourse is situated"
- Regional economic integration organization: an organization constituted by sovereign States of a given region, to which its member States have transferred competence in respect of matters governed by the present Convention and which has been duly authorized in accordance with its internal procedures, to sign, ratify, accept, approve or accede to it"