IRF8 represses neutrophil potential and promotes basophil and mast cell development. Sasaki and colleagues demonstrate that the transcription factor IRF8 interacts with transcriptional partners, such as Ets and/or AP-1 family members, to activate Gata2 expression in granulocytic progenitors, probably through indirect mechanisms. The expression of Gata2 in turn represses production of neutrophils and promotes basophil and mast cell production. Professional illustration by Luk Cox, Somersault 18:24.