V. harveyi is a natural inhabitant of seawater, though it has been documented mainly in the tropics. Unlike its close relative ''Vibrio fischeri'' it is free-living and does not form symbiotic relationships, but is a common pathogen to many marine organisms. In applied science Vibrio harveyi is an integral part of studying inter- and intra-bacterial communication, quorum sensing, as well as bioluminescence. Sequencing of the genome will undoubtedly contribute to further understanding of how bacteria sense the world around them and then make decisions based on their environment. V. harveyi is curved rod shaped, Gram-negative, and monotrichous (mobilized by a single polar flagellum).