Tissue expansion in children has been associated with complication rates of 20 to 40 percent. A critical analysis of 6 years' (1988-1993) experience with 180 expanders placed in 82 consecutive children was performed to identify those factors which predispose to complications. Major and minor complications each occurred in 9 percent of patients. The factors associated with a statistically significant increase in complications were burns and soft-tissue loss, patient age under 7 years, use of internal expander ports, and a history of two or more prior expansions. In addition, complications were significantly more likely to occur within the first 90 days than during any subsequent expansion. Factors that did not influence complication rate included patient gender, wound drainage upon expander insertion or removal, intraoperative use of antibiotic irrigation, number of expanders placed, use of customized expanders, and operating surgeon.