Rigorous impact evaluations of development programs in the environment sector are rare, in contrast to the relatively widespread use of this powerful tool to carefully measure the effectiveness of different strategies in, say, the health and education sectors. This limits our ability to learn conclusively which approaches work best to address some of the world’s most pressing development issues, including responses to global climate change.
Impact evaluations in the environment sector face many of the same challenges as in other sectors, including considerable upfront planning and close coordination across the implementation and evaluation teams. This is especially true when a randomized control trial design — the gold standard of rigorous, scientific impact evaluations — is used. Still, despite its importance, this kind of evaluation is especially difficult to implement in the environment sector, where theories of change typically depend on complex and difficult-to-anticipate changes in ecological systems and human behavior.
Simply put, creating a study that accurately measures how people, groups and environments change in response to specific programs is very difficult. As part of its commitment to evidence-based programming, the U.S. Agency for International Development has found a way to overcome these and other challenges to launch a pioneering RCT in Zambia that will contribute the strongest evidence to date on the relationship between property rights and farmers’ decisions to practice “climate smart” agricultural techniques, such as agroforestry.