The Millennium Villages Project is a high profile, multi-country development project that has aimed
to serve as a model for ending rural poverty in sub-Saharan Africa. The project became the subject
of controversy when the methodological basis of early claims of success was questioned. The lively ensuing debate
offers lessons on three recent mini-revolutions that have swept the field of development economics:
the rising standards of evidence for measuring impact, the “open data” movement, and the growing
role of the blogosphere in research debates.
In this paper, Michael Clemens and Gabriel Demombynes discuss how a new transparency is changing the debate about what works.