To determine current national utilization levels of part-time pediatric residency and to identify reasons for pursuing training on a part-time basis. Data were obtained through (1) a survey regarding part-time residency mailed to all accredited pediatric residency programs, (2) the American Medical Association Fellowship and Residency Interactive Electronic Database, and (3) the American Academy of Pediatrics postgraduate level 3 survey, 2003. Of the 190 accredited pediatric residency programs surveyed, 156 (82%) responded; 18 (12%) of these programs had >or=1 part-time resident during academic years 2000-2003. Nationally, 43 of 6609 residents represented in the survey (0.7%) undertook some of their training on a part-time basis. All programs prorated salaries in proportion to time percentage, 10 (71%) continued full benefits for part-time residents, and 15 (88%) used a reduced call schedule. Although multiple reasons were given for part-time status, including travel (16%), research (14%), advanced degrees (9%), personal illness (9%), and family illness (5%), 67% cited child care as 1 reason. Length of residency was extended by an average of 15 months (range: 4-36 months). Analysis of the American Medical Association Fellowship and Residency Interactive Electronic Database showed that 45 (24%) of 190 programs advertise part-time slots. Although numerous pediatric programs advertise part-time positions, few residents actually held such positions during a 3-year period. There is variability among programs in how benefits and call schedules are managed. Part-time positions are chosen for multiple reasons, but the most common reason is to care for children. Pediatric residency programs can use this information to meet resident needs.