Helge Grosshans and his group at the Friedrich Miescher Institute for Biomedical Research (FMI) have identified two distinct modes of transcription termination – one dependent on, and one independent of, the highly conserved exoribonuclease XRN2. In a fruitful collaboration between wet-lab and computational biologists, they found that the promoter of a gene determines the mechanism for termination of its transcription.