Inadvertent fixation of a presumed bone metastasis may result in tumor contamination, an increased risk of local recurrence, and possibly the loss of limb or life. Although metastatic disease is far more common than primary sarcomas of bone, a rational and consistent approach is important to avoid compromising the patient's outcome. The strategy to make a diagnosis must be separate from that for fixation and reconstruction. Rarely is it possible to combine a biopsy with the reconstruction in a single procedure. Frozen section of a biopsy specimen should be performed before fixation even in patients with a previous history of carcinoma. This is especially important for the first site of osseous metastases.