The substantial increase in recent years in investments in the water and sanitation sector of the Middle East has focused on developing infrastructure in urban areas, with little sustained effort to strengthen the management capacity of sector institutions. This report, based on a review of literature available in the United States, provides on overview of sector institutions in Egypt, Jordan, Tunisia, and the Yemen Arab Republic. The institutional setting of each country's water and sanitation sector is described, including the significant institutions and their organizational make-up, activities, responsibilities, and interlinkages. Sector trends are discussed in terms of programs, investments, and service delivery coverage by responsible institutions. Problems, constraints, and other issues affecting the provision of water and wastewater services are identified. A general framework is provided for examining the status of each country's institutional development in policy environment, appropriate organizational structures, internal and external effectiveness, technology transfer, and use of local capacity and participation. The report identifies areas where pertinent data are limited or lacking. A 54-item bibliography (1975-84) is appended.