Despite the fact that bacteria are single-cellular organisms without a brain, they still have a way to communicate with the rest of their population: quorum-sensing. This also applies to bacteria that can infect humans. These bacteria can in turn be infected by bacteriophages. It is still unclear to what extent quorum sensing helps or hinders bacteriophages. A lot of the research on this topic focusses on two bacterial species: Pseudomonas aeruginosa and Escherichia coli. In both cases, whether quorum sensing helps or hinders bacteriophages depends on the bacteriophage species that the researchers used in the experiment. It is therefore not yet possible to generalise the results of the experiments to give a conclusive answer to the research question of this paper. However, the results of these experiments can be used to further develop phage therapy, in which specific phages can be selected to attack bacteria that are resistant to most, if not all, clinically available drugs.