Sixty-five soybean breeding lines that contain IAC-100 in their pedigrees plus three cultivars were examined for potential resistance to stink bug feeding and lepidopteran defoliation in 2001 and 2002. The IAC-100 cultivar is reported to have resistance to the stink bug complex in South America, thus soybean crosses were made at Virginia Tech with this cultivar as a parent. From the responses of the 68 entries in the initial trial, 28 entries were selected for continued evaluations in 2003 and 2004. These entries had the lowest stink bug damaged kernels, lowest percentage defoliation and/or the highest yields. In 2005, twelve entries were included in the advanced resistance study. From this five-year study, four entries were identified as having the best resistance to stink bug feeding plus five entries were identified as having the best resistance to lepidopteran defoliation. These lines will provide excellent sources for future soybean varietal resistance development.