The framework for water accounting is applied to an international river basin, the Orange River Basin, which is shared among Botswana, Namibia, Lesotho and South Africa. Each of the riparian states faces water constraints and relies increasingly on shared international water resources. The countries have adopted the principle of an economic approach to water management, once basin human needs are met, and all but Lesotho have constructed national water accounts to assist in water management. The water accounts for the Orange River Basin bring an economic perspective to water management at the regional level. The accounts include supply and use tables, which are used to compare the contribution to water supply from each riparian state to the amount used. The water accounts are then linked to economic data for each country to calculate water use and productivity by industry and country. There are considerable disparities in water productivity among the countries, which should be taken into account in future decisions about water allocation, pricing and infrastructure development. Keywords: Environmental accounting, Water resource accounts, River basin management, Africa, Water productivity.