Limited English proficiency (LEP) is a common barrier that negatively affects access to health care and quality of care. Prior studies have examined interpreter services as a means of ameliorating LEP, but have focused on Spanish-language services, largely overlooking comparisons with other, less-established ethnic groups. Furthermore, few if any studies have assessed the quality of interpreter services provided. Data come from 2,489 Hispanic/Latino, Hmong, and Somali enrollees of public health insurance programs in Minnesota. We employ weighted, regression-adjusted comparisons of enrollee-reported need and availability of interpreters, access to professional and consistent interpreters, and problems with quality of interpreter-assisted communication. Compared with Latinos, Hmong and Somali enrollees reported greater needs and more communication problems, Somali enrollees reported lower availability, and Hmong enrollees reported lower access to professional interpreters. Further training of interpreters for relatively less-established ethnic groups is needed to increase availability of professional, high-quality communication among publicly insured ethnic minorities.