Oh lazy sister, where art thou?

Mitotic divisions achieve equal re-partition of chromosomes into daughter cells. In their recent work in Developmental Cell, Sen, Harrison et al. propose that the risk of mis-segregation in human mitotic cells is higher than previously thought and identify the existence of an early-anaphase correction mechanism. The study documents kinetochore dynamics in unprecedented detail, providing a detailed look at the events preceding loss of correct chromosomal numericity and genomic stability.