Insects that attack stored products can cause severe damage and economic loss. Chemical controls are used widely to reduce damage, but new restrictions threaten the use of many compounds because of potential harm to human health and the environment.  Biological control agents are a potential alternative. Many of the problems in stored product commodities are related to insects surviving control measures, typically as a result of hiding in refugia and cracks and crevices in storage containers.  Entomopathogenic nematodes have the ability to find and infect hosts in cryptic habitats, but have not been tested in stored product environments such as empty grain bins or food processing and warehouse facilities.  The first step in developing a control program with entomopathogenic nematodes is to determine their pathogenicity against the range of pest species most commonly encountered in storage conditions.  Three nematode species (Steinernema riobrave, S. carpocapsae and S. feltiae) were evaluated for their pathogenicity against larvae, pupae and adults of eight pest species (Plodia interpunctella, Ephestia kuehniella, Sitophilus oryzae, Ryzopertha dominica, Tribolium castaneum, Oryzaephilus surinamensis, Trogoderma variabile, and Tenebrio molitor).  S. riobrave was either the most pathogenic or of similar pathogenicity compared with the other nematode species tested, except against T. variabile.  The high pathogenicity exhibited by S. riobrave as well as its relative tolerance of high temperature and low humidity makes it a great candidate for further testing under storage conditions.