This retrospective study aimed to assess the usefulness and clinical importance of current, commonly used, diagnostic staging procedures in breast cancer. The analysis comprises all 398 women clinically staged I-III (UICC criteria), and irradiated with radical intent in the Professorial Unit of Radiotherapy at the Middlesex Hospital over a ten-year period (1978-1987). The routine initial screening in this institution included the following staging investigations within 4 weeks of referral: 99mTc MDP bone scan; chest X-ray; liver function tests (including serum alkaline phosphatase) and liver ultrasound scan. Further enquiry and examination of the patient, clear progression of disease, additional radiographs or a recommended repeat interval scan provided sufficient additional information to confirm metastatic disease. The overall rate of detection of metastatic disease at three months was 29/389 (7.4%) for skeletal scintigraphy, 10/386 (2.6%) for chest radiographs, 8/271 (2.9%) for liver ultrasound and 3/347 (0.8%) for serum alkaline phosphatase. In total 37/398 (9.3%) of patients were confirmed to have metastatic disease by three months. Skeletal scintigraphy alone appears to identify 78% (29/37) of those with detectable metastatic disease at 3 months. Skeletal scintigraphy and liver ultrasound will identify 95% (35/37).