Promyelocytic leukaemia nuclear bodies (PML-NBs) are one of numerous distinct subnuclear structures that are thought to compartmentalize the nucleus. They contain the PML protein and are associated with various nuclear functions, including transcriptional regulation, apoptosis and the maintenance of genome stability. Now, Stig Ove Bøe and co-authors report that PML-NBs are predetermined processing sites for damaged DNA (see p. 3284). The authors use time-lapse confocal imaging to show that foci of single-stranded DNA (ssDNA) colocalize with preformed PML-NBs within an hour of exposure of cells to UV irradiation. Furthermore, they report, RNAi-mediated depletion of PML (which causes PML-NBs to disappear) prevents formation of these foci after UV exposure. It also sensitizes the cells to UV-induced apoptosis and inhibits S-phase progression in the presence of DNA damage caused by etoposide. Because PML-NBs are present even in unperturbed cells and contain several DNA repair proteins, the authors conclude that they are processing sites for damaged DNA, whether this is produced during normal DNA replication or in response to stresses such as irradiation.