Collection of race, ethnicity, and primary language data of health plan members is a recognized important step in addressing disparities in health care. The authors conducted six focus groups to examine perceptions of Massachusetts consumers about collection and use of race/ethnicity and language data by health plans, preferences for how and when the data should be collected, and preferences for racial/ethnic categories. Consumers understood the utility of collecting primary language data from members but expressed concerns about the collection of race/ethnicity data. Despite these concerns, they provided suggestions for using the data to improve care. Their preferences for racial/ethnic categories suggested that they wanted a balance between simplicity and reasonable granular detail. Ultimately, consumers wanted to be assured that the information they provided to health plans would be used to improve quality, and they wanted to be able to provide this information without undue burden and with assurances of confidentiality.