Malodor generation from swine manure is complicated by the involvement of many bacterial species that produce an extneive array of volatile organic compounds (VOC’s) A lack of understanding of the basic manure microbiology further complicates the problem. This review covers pertenint detailed information about indigenous bacteria generea in swine manure and their poentail for producing odourous volatile compounds. It addresses not only the odorous compounds in swine manure but also the relations between bacterial species and related compounds. It apperas the volatile fatty acids may be the major odorous compounds in swine manure, and two bacteria genera. More research is needed to identify the bacterial species within these two genera to better understand the kinetics of melecular production by the bacteria.