The Type VI secretion system (T6SS) is a contact-dependent killing mechanism employed by many bacteria, including V. cholerae, P. aeruginosa, and several strains of V. fischeri, in competition for a niche. While interactions between T6SS+ and T6SS- strains are clearly defined and well studied, my project looks into interactions between two different strains that both have T6SS. This holds applications in studying competition mechanisms in larger microbiomes and in pathogenesis.