As one of the largest multilateral donors for environmental programs, STAP believes the GEF should be a leader in the production of evidence. With multi-nation investments in common environmental policies and programs, the GEF is uniquely placed to generate credible evidence about improving the performance of these programs. Such evidence would not only increase returns to GEF investments, but it can also catalyze broader investments and actions by making the connection between environmental investments and the effects of these investments clearer to external audiences.

This advisory document describes one important way in which the GEF can leverage its project investments, to be better informed about what works and under what conditions. Experimental project design implys that entire projects, or components of projects, are designed with the intention of better understanding the causal relationships between project actions and desired effects.

Experimental project designs that test important hypotheses about project implementation are at the nexus of science and project management. They thus contribute less to traditional environmental science and more to a form of adaptive, implementation science that applies scientific principles to enhance our understanding of how the generation of results from project implementation can be improved.