Purpose: The purpose of this study was to investigate (a) whether certified nursing assistants (CNAs) are more committed to nursing home jobs when they perceive their jobs as enhanced (greater autonomy, use of knowledge, teamwork), and (b) whether CNA job commitment affects resident satisfaction. Design and Methods: A qualitative exploration of management philosophy and practice and of CNAs' views of their jobs in 18 Massachusetts nursing homes formed the basis for a survey administered to 255 CNAs in 15 homes. A quality-of-life questionnaire was administered to 105 residents. Logistic regression accounting for clustering estimated the effect of personal characteristics, satisfaction with tangible job rewards, and aspects of job design on CNAs' intent to stay in current jobs. A general linear model estimated the effect of job commitment on residents' satisfaction with their relationship to nursing staff. Results: After we accounted for satisfaction with wages, benefits, and advancement opportunities, good basic supervision was most important in affecting CNAs' intent to stay in their jobs. Job enhancements were not significantly related to intent to stay. Residents were more satisfied with their relationships to nursing staff and their quality of life on units where a higher proportion of CNAs were committed to their jobs. Implications: The finding that greater job commitment of CNAs is associated with better quality of relationships and life for residents implies that better jobs lead to better care. Culture change transformation that increases CNA autonomy, knowledge input, and teamwork may not increase workers' commitment to jobs without improvements in basic supervision.