Appropriateness of drug use is an important indicator of the quality of care in nursing homes. In this study, we analyzed the influence of resident characteristics and selected organizational factors on the appropriateness of psychotropic drug use in 33 Swedish nursing homes. Specific criteria based on published guidelines and recommendations were developed to measure appropriateness. Residents diagnosed with a psychiatric disorder and younger residents had more deviations from the criteria; however, resident mix did not explain variations in appropriateness of drug use at the facility level. Facilities with better nurse staffing and drug intervention teams had fewer deviations from the criteria, but only 15-20% of the variation in drug prescribing was explained by these predictors.