At 3ie, our mission is to fund the generation and sharing of sound, useful evidence on the impacts of development programmes and policies work. Actually, we’re more curious (or nosy) than that. For impact evaluation that matters, we need to know which bits of a programme worked, which didn’t, why and through which mechanisms, in which contexts and for what costs.

Over the last week, 3ie staff in Delhi, London and Washington were busy coordinating conference logistics, finalising the conference programme, figuring out how to balance 3ie publications and clothing in their suitcases, and putting the last touches to their presentations. This is usual conference preparation for a conference that is going to be different. Why is this conference different? The participant mix – more than 500 people – is balanced among policymakers, programme managers and implementers, and researchers.

A couple of months back the BBC reported a new study which questioned existing advice to eat five portions of fresh fruit and vegetables a day.  Five was not enough according to the study authors, it should be seven.  I really do try each day to eat five portions. Where was I going to find the time and space for these extra two portions?  But this looked like a sound study published in a respected academic journal, with data from over 65,000 people.