OBJECTIVE: The objective of this study was to support home health agencies (HHAs) in the United States (US) in their individualized quality assessment and performance improvement (QAPI) initiatives by identifying their key performance improvement domains (KPIDs). METHODS: Qualitative research was conducted by following the Framework method. Rich contextual data were obtained through focus group meetings participated by domain experts. The analysis results were further refined in an online forum and validated at a final meeting. RESULTS: Four focus groups involving a total of 20 participants resulted in useful discussions during which various perspectives were expressed by the expert participants. A well-defined set of 17 KPIDs emerged under four categories, namely, economical value, sociocultural sensitivity, interpersonal relationships, and clinical capabilities. CONCLUSIONS: The feedback we received from the focus groups indicates that performance improvement in HHAs is a lot more complicated than simply assessing whether certain clinical tasks are performed. The KPIDs identified in this study can help HHAs in their focused and individualized QAPI initiatives. Therefore, the results should be immediately relevant, interesting, and useful to the home care industry and policy makers in the US.