International waters demand collective action, and this evaluation examines whether GEF projects from 1991–2000 laid foundations for lasting transboundary progress.

The 2002 Program Study on International Waters, prepared as an input to the Second Overall Performance Study (OPS2), reviewed 45 projects totaling $444 million, with 11 completed at the time. Drawing on portfolio review, field visits, consultations, and participation at the first GEF Biennial International Waters Conference, the study assessed alignment, achievements, and challenges.

It finds the portfolio balanced across regions, consistent with Council guidance, and contributing to international agreements and action plans on freshwater and marine ecosystems. Some completed projects show reductions in marine stress, but the absence of uniform tools for comparing pollution sources limited portfolio-wide assessment. Demonstration projects were generally well conceived, though most impacts remained at the process level, reflecting the long time needed for measurable improvements.

The report recommends strengthening monitoring and evaluation, clarifying operational guidance, improving lesson learning and interagency coordination, and subjecting high-risk projects to midterm review.