Pyrrhalta viburni, an invasive chrysomelid native to Europe first detected in the USA in Maine in 1994, is becoming a major landscape pest in the northeast and poses a serious threat to a large portion of the U.S. Both larvae and adults feed on shrubs in the genus Viburnum, and can kill susceptible plants within a few years. Plants in both managed landscapes and natural areas are at risk. Of the various biocontrol agents we have evaluated in the laboratory, Podisus maculiventris has shown the greatest promise; nymphs consumed more than 90 viburnum leaf beetle larvae during their development in laboratory assays. Trials have been done to evaluate predatory efficacy in field settings on both caged and open-grown plants. Predatory efficiency of Podisus maculiventris is correlated with size of shrubs and pest density. Pest larval populations are significantly reduced when infestations are light, but no effect is seen when infestations are heavy. Other parameters, such as temperature, presence of refugia, and presence of other predators may also influence predatory efficiency and have been looked at. These results suggest that P. maculiventris may be useful in augmentation biological control programs for viburnum leaf beetle subject to several constraints of environment and release conditions.