The twenty-first century experimenting society: the four waves of the evidence revolution

This paper presents a personal perspective–drawing especially on the author’s experience in international development—of the evidence revolution, which has unfolded in fours waves over the last 30 years: (1) the results agenda as part of New Public Management in the 1990s, (2) the rise of impact evaluations, notably randomized controlled trials (RCTs) since the early 2000s, (3) increased production of systematic reviews over the last ten years,...