WHAT'S KNOWN ON THIS SUBJECT: Language barriers adversely affect health care access, utilization, outcomes, and patient safety. Trained formal interpreters can improve care quality and safety, but many patients and families with limited English proficiency do not receive appropriate language services during health care encounters.WHAT THIS STUDY ADDS: Despite continued growth of the US population with limited English proficiency, federal language use standards, and enhanced education about appropriate use of language services, there has been only modest improvement over time in pediatricians' use of language services. RESULTS: Most pediatricians reported using family members to communicate with LEP patients and families, but there was a decrease from 2004 to 2010 (69.6%, 57.1%, P , .01). A higher percentage of pediatricians reported formal interpreter use (professional and/or telephone) in 2010 (55.8%) than in 2004 (49.7%, P , .05); the increase was primarily attributable to increased telephone interpreter use (28.2%, 37.8%, P , .01). Pediatricians in states with reimbursement had twice the odds of formal interpreter use versus those in nonreimbursing states (odds ratio 2.34; 95% confidence interval 1.24-4.40).CONCLUSIONS: US pediatricians' use of appropriate language services has only modestly improved since 2004. Expanding language services reimbursement may increase formal interpreter use. Pediatrics 2013;132:e396-e406 AUTHORS: