All living cells divide by faithfully transmitting genetic information from one cell generation to the next. This extraordinary process is tightly regulated in order to prevent unequal segregation of chromosomes and genetic imbalance, which can lead to genomic instability and cancer. Although our knowledge of the proteins involved in choreographing this process is quite advanced, recent scientific observations have revealed that new players are also involved in this tightly regulated cellular process. Here, we have uncovered a potential role in mitosis for a protein, DNA-PK, which was previously known to function only in the repair of DNA damage. We will characterize the role of DNA-PK in mitosis, which will expand our understanding of the mitotic checkpoint and could lead to identification of novel targets for therapeutic intervention that will ultimately improve outcomes in cancer patients.