The Stockholm Environment Institute is an international not-for-profit research organisation that aims to promote sustainable development through scientific analysis that supports decision-making on the national and international level. It focuses on four broad themes: reducing climate risks; managing land, water and air resources; improving governance; and developing new visions and pathways to development. The website provides free access to the institute's publications, describes current projects and links to useful modelling or policy tools such as LEAP (the Long-range Energy Alternatives Planning system) and IPAT-S.

WaterAid is an international nongovernmental organisation dedicated to using low-cost technologies to improve access to safe water, hygiene and sanitation in the world's poorest communities. Its website addresses the need for improved water resources, provides statistics on water sanitation and hygiene, highlights case studies of the organisation's work and provides a comprehensive library of policy, advocacy and research publications.