Nadia Rosenthal is an example of the reverse brain drain. Her move, just under a year ago, from Harvard Medical School to the European Molecular Biology Laboratory (EMBL) in Monterotondo was triggered by the transfer in the opposite direction of Klaus Rajewsky. She now has his old job running EMBL's mouse research program, and he has moved to Harvard (Nature Med. 7, 392; 2001). Rosenthal shared her views of the two research settings with Nature Medicine.