[영문]Using data from the 2003 national Online Survey Certification and Reporting System, this study examines how the structure of social service staffing in nursing homes is affected by organizational and contextual factors. The results suggest that, although federal regulations impose minimal obligation, requiring only facilities with more than 120 beds to employ qualified social service providers, nearly 12 percent of these facilities failed to meet this staffing requirement in 2003. Results further suggest that the skill mix of social service providers in nursing homes is influenced by market competition, market demand, facility ownership, aggregate resident acuity, and the proportion of facility residents funded by Medicare