The use of heat to control insects in flour mills and other food-handling establishments was proposed more than six decades ago (Goodwin 1922, Pepper and Strand 1935). Fields (1992) provided a comprehensive review of literature on the control of stored-product insects and mites with extreme temperatures. Heat is a viable alternative to methyl bromide. Heat usually distributes well in a facility, although it will not penetrate materials like grain and flour. It is relatively safe in that personnel can move freely within a facility during a heat-up, and portions of food-handling establishments that are not being heated can still be operational. A heat treatment does not leave any toxic residues. K-State research results on heat since May 1999 are posted at the following web site: http://www.oznet.ksu.edu/dp_grsi/heattreat.htm. Typically heat supplied by gas, electric, or steam heaters is used to raise the temperature within the food-handling establishment to 50oC, and this temperature is held for 24-36 hours to kill insects inside machinery and in building cracks and crevices. Eight species of insects exposed to a heat treatment died within 4 hours during August 4-6, 1999 heat treatment of K-State’s flour and feed mills. Insect traps placed throughout mills before and after heat treatment showed >90% reduction in insect populations following a heat treatment. Better assessment of insect populations within mill machinery and in raw ingredients is needed to accurately gauge heat treatment effectiveness. We propose to develop a degree-hour model to predict insect mortality during a heat treatment. Laboratory experiments at several constant and variable temperatures, simulating an actual heat-up, will be performed in a programmable oven to establish a base temperature to start accumulating degree-hours. This model will be validated during actual heat treatments in K-State’s pilot mills and in commercial food-handling establishments. A better understanding of occurrence and dynamics of insect populations will be obtained by sampling static grain and flour residues from floor and within mill machinery. The K-State’s pilot mills and commercial food-handling establishments will be a part of this study. Assessment of populations from these residues will be compared with trap catches. A better assessment of insect populations within food-handling establishments is needed to gauge treatment effectiveness with heat or any other control measure. Our research will also develop cost-benefit analyses for heat treatments.