The Aral Sea Basin, which is shared by 5 countries of the former Soviet Union - Kazakhstan, Kyrgyzstan, Tadjikistan, Turkmenistan and Uzbekistan is well known to the world due to the large scale water development in the Soviet period, which caused many ecological problems in the region. One of them is the problem of return waters, which are unmanaged and unused in now acceptable form. The total Transboundary Return Water (TRW) volume formed in the territory of 5 states is 36-40 km(2). The two main reasons for the worsening of water quality in the major rivers of the Aral Sea basin - Amudarya and Syrdarya are: water withdrawal from the rivers for irrigation purposes and release return flow to the river of a large content of salts and other pollutants from irrigated lands. Spontaneous formation, dissemination and accumulation of return waters can, and already have caused considerable negative effects in environment and social development. For the development of a program for the use and management of these waters and its approval by the region's countries, measures preventing these effects must be taken in order to be of mutual benefit to all the countries involved and, simultaneously, to transform these waters into a source of life, biodiversity, sustainability and prosperity in the Aral Sea basin on a scale, that would influence the world community. For stabilization of these water bodies at the regional, and, thus at a global scale, it is necessary to eliminate the following threats: instability of whole scope and especially TRW regime in terms of quantity and quality; uncontrolled allocation and use of such waters; injurious use, including poaching. It must be taken into account that transboundary waters' sustainable development and use require permanent monitoring and management over a range of criteria, providing their ecological stability and safety as well as long-term bioproductivity and biodiversity of ecosystems supported by them. The principle provisions of management system on TRW are proposed for each stage: type of return water use; direction of possible use; stability criterion; restrictions; control.