All organisms incur damage to their DNA in the course of their daily lives and have developed sophisticated mechanisms for DNA repair. Many of the enzymes involved in these DNA repair pathways have been identified and their biochemical activities are well understood. However, there is a relatively poor understanding of how these enzymes are put into play in response to DNA damaging agents. The goal of my work was to better understand the anti- and pro-mutagenic DNA repair pathways in live Escherichia coli cells. My focus here is on the interplay between the error-prone DNA polymerase II (pol II) and it’s binding partners, in particular the beta-sliding clamp. Utilising single-molecule fluorescence live-cell imaging, it has been possible to monitor the activities of these proteins in real time to gain new insights into their behaviour.