Bacteria from the genus Wolbachia ensure their transmission to the offspring of their insect hosts by influencing the hosts in many ways, including altering their reproduction. This study reveals the mechanism by which the bacteria achieve this. Using the Wolbachia strain that infects Drosophila mauritiana (Wolbachia wMau), the authors found that the bacteria preferentially accumulated at the germline stem cell niche (GSCN). The presence of Wolbachia wMau was found to affect GSC function, resulting in the production of significantly higher numbers of eggs than were produced by non-infected flies. The resultant enhanced egg production was due to an increase in GSC proliferation caused by Wolbachia wMau, as well as a decrease in developmentally regulated apoptotic events in the fly germarium (the egg-producing portion of the ovary).