This work describes the development of a pediatric quality of care measurement system designed to cover multiple clinical topics that could be applied to enrollees in managed care organizations and to compare the development of this system with the concurrent development of a similar system for adult women. Indicators were developed for 21 pediatric (ages 0-18) years) clinical topics and 20 adult (ages 17-50 years) women's clinical topics. Indicators were classified by the strength of evidence supporting them. Of 557 pediatric and 391 adult women's proposed indicators, 453 (81%) and 340 (87%), respectively, were retained by the two expert panels. This study contributes to the field of pediatric quality of care assessment by providing many more indicators than have been available previously and by documenting the strength of evidence supporting these indicators. Formal consensus methods are essential for the development of pediatric quality measures because the evidence base for pediatric care is more limited than for adult care.