Quantitative digital radiography (QDR) is a new technique for measuring bone mineral content that offers improved precision, shorter study times, and less radiation exposure than single-photon absorptiometry (SPA), dual-photon absorptiometry (DPA), and quantitative computed tomography (CT) scanning. To evaluate application of QDR to a pediatric population, the bone mineral density (BMD) of both proximal femurs and lumbar spine was determined in 20 normal children aged 4-15 years. Duplicate measures indicated a precision less than 2%. A small left side/right side difference was sometimes found in the BMD of the proximal femurs. This difference was not related to age, sex, or handedness, and there was no history of significant injury to, or problems with, either lower extremity. QDR will greatly enhance early evaluation and treatment of many conditions that adversely affect the immature skeleton.