A latent segmentation modeling is used in this study to identify theheterogeneity of willingness-to-pay estimates for quality attributes andcountry-of-origin in the Korean beef market. Three distinctive groups ofgrocery shoppers are identified based on their level of concern (very,moderately, and not too concerned) about the use of antibiotics andgenetically modified organism feed ingredients in beef production. Resultsindicate that the very concerned group values such attributes asantibiotics-free, genetically modified organism-free, and domesticproduction the most among the three groups. Results also suggest that themost important factor in determining grocery shoppers' willingness-to-pay iscountry-of-origin for all three groups.