The radiological appearance of giant cell tumors (GCT) in the developing skeleton was retrospectively assessed in 49 (10.6%) of the 462 patients with GCTs seen in consultation by the Netherlands Committee on Bone Tumors. There were 31 female and 18 male patients, all below 19 years of age. Thirty-four tumors were located in short and long tubular bones, two in the tarsus, while the others were in the pelvis, vertebral spine, and a rib. Involvement of the epiphysis in tubular bones was closely related to the age of the patient: the average age of the 3 patients with a lesion in the metaphysis was 11 years, that in the 6 patients with metadiaphyseal lesions 13 years, average age in the 10 patients with epimetaphyseal lesions 17 years, and it was also 17 years in the 17 patients with epimetadiaphyseal lesions. In tubular bones with the epiphyseal growth plates still open, the epiphysis was never involved, with the exception of two epimetadiaphyseal lesions in which closure of the growth plate was difficult to establish. Assessing GCT characteristics in this study population demonstrated that epiphyseal involvement increased with age and showed; to some extent, a predominance of female patients.