Three children with osteogenesis imperfecta, severe osteopenia, and repeated fractures were treated with cyclic infusions of aminohydroxypropylidene bisphosphonate (pamidronate) for a period ranging from 22 to 29 months. A clear clinical response was shown, with a striking reduction of new fracture episodes and a marked improvement in the quality of the patients' lives. Bone mineral density increased significantly in two patients, and linear growth continued along the percentile at the start of treatment. There were no adverse effects of note during treatment, and further studies are warranted.