This is an evaluation report of the United Nations Research Institute for Social Development (UNRISD). The evaluators found that UNRISD's research output meets high standards of scientific quality, even if it varies somewhat. However, most of UNRISD's work is not very original in the strictest scientific sense of theoretical or methodological breakthroughs, and cannot be said to be at the cutting edge of knowledge production. UNRISD is at its best when advancing novel perspectives and approaches to the analysis of social phenomena. The contributions regarding popular participation in development processes and the analytical perspectives on environmental problems in the interface of social systems and natural ecosystems, stand out as particularly significant. Generally, UNRISD has advanced the professional and public debate considerably. The evaluation team founds, furhermore, that most of UNRISD's research findings have high societal relevance, but it is largely potential because it relates to a global public which is a diffuse constituency. UNRISD has been effective in keeping key issues - often complex and controversial ones - on the development agenda. The Institute has both generated and induced new thinking on social development, often researching and publishing on crucial topics well before they were recognised as important. As such UNRISD has been a significant player in shaping the development debate in the course of the last thirty years.