Posting for a friend. If you are someone who is interested in development work in the long term, especially at an organization like the WB (though if that's not representative then think other dev organizations) then the following questions:

1. Is a PhD the right path, or is an MPA/ID better? What career can you have in development without a PhD?
2. If a PhD is the right path, what kind of PhD? Obviously an econ PhD is good, but can a public policy PhD/polisci PhD also achieve the same path? I know econ has more option value in areas beyond dev, but assume the focus is only on dev.
3. If a PhD in econ is the right path, what is the lower bound on program ranking that is worthwhile? Assume you have no interest at all in a TT research position and are certainly going for a development job.