Health plan members who did not need an interpreter in the past 6 months were compared with those who needed one and always, usually, sometimes, or never got one. In multivariate analyses, Hispanic and Asian/Pacific Islanders (API) members who needed interpreters and usually, sometimes, or never used one reported significantly worse (p < .05) provider and office staff communication, access to care, and health plan customer service compared with members who did not need interpreters. Hispanic and API members who needed and always used an interpreter reported similar or significantly better (p < .05) provider and office staff communication, access to care, and health plan customer service than members that did not need interpreters. Use of interpreters reduced White-Hispanic disparities in reports of care by up to 28 percent and White-API disparities by as much as 21 percent. Increasing use of interpreters could reduce racial/ethnic disparities and improve health plan performance. © 2006 Sage Publications.