One hundred ninety patients with breast cancer were prospectively evaluated for bone pain and had technetium Tc 99m-methylene diphosphonate bone scintigraphy for bone metastases. Of the 66 patients showing evidence for bone metastases, 21 (32%) did not have bone pain. There were 155 sites of skeletal metastases, but pain was found only in 50 sites. The age of the patient or involvement of weight-bearing bones did not seem to affect the association between bone metastases and pain. We discuss the need for periodic bone scintigraphy, even when the clinical state does not seem to warrant it.