Context: Quality measures focused on outpatient settings are of increasing interest to policy makers, but little research has been conducted on hospital outpatient quality measures, especially in rural settings. Purpose: To evaluate the relevance of Centers for Medicare and Medicaid Services' (CMS) outpatient quality measures for rural hospitals, including Critical Access Hospitals. Methods: Researchers analyzed Medicare hospital outpatient claims and Hospital Compare outpatient quality measure data for rural hospitals to assess the volume of conditions addressed by the measures in rural hospitals. A literature review and information from national quality organizations were used to assess the external and internal usefulness of the measures for rural hospitals. A panel of rural hospital quality experts reviewed the measures and provided additional input about their usefulness and data collection issues in rural hospitals. Results: The rural relevant CMS outpatient measures include most of the Emergency Department (ED) measures. The outpatient surgical measures are relevant for the majority of rural hospitals providing outpatient surgery. Several measures were not selected as relevant for rural hospitals, including the outpatient imaging and condition-specific measures. Conclusions: To increase sample sizes for smaller rural hospitals, CMS could combine data for similar inpatient and outpatient measures, use composite measures by condition, or use a longer time period to calculate measures. A menu of outpatient measures would allow smaller rural hospitals to choose relevant measures depending on the outpatient services they provide. Global measures and care coordination measures would be useful for quality improvement and have sufficient sample size to allow reliable measurement in smaller rural hospitals.