Context: Migrant and seasonal farmworkers are recognized as a medically underserved population, yet little information on need, access, and services is available--particularly with regard to oral health care. Purpose: This study describes the facilities, services, staffing, and patient characteristics of US dental clinics serving migrant and seasonal farmworkers, and identifies trends and issues that may impede or improve dental care access and service. Methods: National databases were used to identify community and migrant health centers providing oral health care to migrant and seasonal farmworkers. Mailed surveys collected information on clinic history, operational details, services provided, patient demographics, employment and resource needs, and perceived barriers to care. Findings: Among the 81 respondents (response rate 41%), hours of operation varied from 1 evening a week to more than 40 hours a week; 52% had no evening hours. Almost all the clinics offered preventive, diagnostic, and basic restorative dental services, and roughly two thirds also offered complex restorative services. Patients most frequently sought emergency dental care (44%) followed by basic restorative services (32%) and preventive services (26%). The dentist position was the most difficult to fill, and new funding sources were cited as the most important resource need. Respondents perceived cost of services, lack of transportation, and limited clinic hours as primary barriers to care. Conclusions: While some barriers to care have been almost universally addressed (eg, language), there is evidence that some impediments remain and may present significant obstacles to a broad improvement in oral health care for migrant and seasonal farmworkers.