How much cooperation exists across ethnic lines in East Africa? And how is this cooperation affected by political circumstances and messages? This project, which is joint with several co-authors (Lars Ivar O. Berge, Kjetil Bjorvatn, Simon Galle, Dan Posner, Bertil Tungodden, Kelly Zhang), uses evidence from lab experiments in Nairobi, Kenya and Dar es Salaam, Tanzania to begin to answer these important questions.