As a subcontractor to Yale University, Sundance Research Institute used a modified CAHPS survey approach to identify opportunities for IHS quality improvement. The purpose of this project was to demonstrate the potential usefulness of a modified CAHPS survey approach to identify opportunities for IHS quality improvement (QI). Two Indian Health Service Units, working collaboratively with their respective Tribal Health Departments and Sundance Research Institute, developed a modified CAHPS survey instrument that retained the core CAHPS measures and added questions reflecting the unique characteristics of IHS services. Both Service Units were also participating in the IPC II initiative; one Service Unit designed a targeted QI initiative based on the CAHPS survey results, and the other Service Unit served as a control site for the project. The baseline American Indian CAHPS survey was administered in mid-2010 to 400 IHS patients at each site, and the results were used by the joint IHS-Tribal Working Group at the intervention site to identify areas for improvement and significant factors associated with overall rating of IHS services. This information was used to develop specific QI initiatives focused on customer service that were implemented in 2011. Sundance Research Institute provided support and assistance to the design of the QI initiatives and monitored ongoing implementation and related activities through site visits and key informant interviews. A follow-up American Indian CAHPS survey was conducted in spring 2012 to assess the impact of the targeted QI initiative on patient ratings of Service Unit performance in the targeted dimensions of service and on overall patient satisfaction. Survey results indicated a statistically significant increase in patient ratings of IHS staff courtesy and helpfulness and in overall rating of IHS services.