Through development of a conceptual model and an index measure based on actual performance, this dissertation focused on clarifying what is "very good" (and "very bad") in nursing home quality. The model expanded on the traditional narrow image of nursing home quality of care, and specified four major dimensions of this broader view of quality. The dimensions (staff intervention, nutrition/food service, physical environment, and community relations) were each reduced further to two subdimensions. Factors influencing quality were also delineated. The new model was then used to tie specific measurable indicators to the overall quality construct. Quality indicators derived from standardized assessments of Medicaid residents were employed in a study of 135 intermediate care facilities in Virginia. Process variables, such as use of physical restraints, catheters, and receipt of various therapies, were analysed for 12,327 residents. Outcome variables (weight loss, increased dependencies in activities of daily living, new pressure sores) were determined through longitudinal analysis for residents with an appropriate preceding assessment (n = 9,006). Assessments were aggregated in each home to calculate a mean (percentage incidence) for each of the 14 quality indicators. A scaling system was used to clearly identify industry"norms" for each variable. Quintiles based on relative incidence were employed to assign homes to five levels of performance. Scale scores were summed to obtain a facility index measure of relative quality. Reliability and validity were evaluated. Relationships of case-mix and selected structural variables (size, ownership, location, percent Medicaid, staff ratios) to the quality measure were analysed. Results suggested better performance by non-profit and smaller homes, but proprietary and non-prof it facilities were about evenly represented among the top tenth percentile of homes. Presence of a skilled care unit appeared to negatively influence quality. Possible interactions and explanations for this finding were considered. Most significantly, the study demonstrated that resident assessments can serve as excellent information sources about what goes on in nursing homes. However, additional variables must be incorporated to make a comprehensive quality measure, based on the model. Recommendations and policy implications were discussed. / Doctor of Philosophy