Inconsistent performance of biological control strategies for turfgrass disease control has limited the adoption of this technology into IPM programs. A major factor contributing to this variable performance in agricultural systems is the cultivars to which biological control organisms are applied. In the proposed study, our goal was to determine whether biological control activity of introduced inoculants was affected by the creeping bentgrass cultivar to which they were applied. We reasoned that biological control performance should be enhanced on cultivars that are less susceptible to the disease in question as opposed to highly susceptible cultivars. The short-term applied goal of this research was to develop the understanding of how we might maximize the performance of microbial inoculants in turfgrass systems. The objectives of our research were to 1) determine the differential susceptibility of bentgrass cultivars to Pythium aphanidermatum and 2) determine the efficacy of known microbial inoculants in controlling Pythium damping-off on different bentgrass cultivars. The results of this study will ultimately be critical in making sound IPM recommendations for creeping bentgrass cultivars that will be most compatible with biological control strategies.