Old World primates are often studied to model human skeletal physiology. An important advantage of monkeys over other animal models (i.e., rodents) is the presence of cortical bone Haversian remodeling. Seventy-five female rhesus monkeys (Macaca mulatta) were subjected to bone biopsy. With monkeys in lateral decubitus position, the tenth rib was surgically exposed and freed from periosteum by use of careful sharp and blunt dissection. The rib section was resected, using bone cutters, and the surgical wound was closed. This procedure was repeated for the contralateral rib at a later time point in 65 monkeys. There was no mortality or appreciable morbidity. The bone specimens were (mean +/- SD) 2.50 +/- 0.25 cm long, with 5.5 +/- 1.0 mm2 total cross-sectional area. They were adequate for histologic, immunohistochemical, and quantitative histomorphometric examinations. Prevalence of pneumothorax was approximately 8.0% for the 140 procedures. This complication was immediately and successfully corrected by insertion of a small thoracic tube, evacuation of pneumothorax, and closure of the incision. This well-tolerated, repeatable procedure yields excellent specimens for performance of cortical bone histologic examination without euthanasia, allowing longitudinal evaluation.