As the vehicle for inherited information, maintaining the quality of the information stored in the genome is a key activity undertaken by the cells of all organisms. This requires maintaining both the genetic sequence and number of chromosomes. Understanding how cells reproduce an exact replica of their genome, and repair damage when it occurs, continues to be a focus of researchers across Oxford. There is a diverse array of errors that can occur during the process of replication, as well as in response to environmental factors such as chemicals and radiation. Subsequently, the ways in which cells detect and repair them are equally varied. Mechanistic insights into these pathways are key to understanding how their defects contribute to tumour development and a patient’s response to different types of therapy.