The relationship between presenting skeletal X-ray findings and survival in multiple myeloma was assessed in 172 consecutive patients treated at this institute. All patients were investigated, treated and followed up according to one protocol. The shortest survival was seen in those with normal X-rays (3-year actuarial 11 per cent) and the longest in those with minimal lytic changes (3-year actuarial 44 per cent). Patients with osteoporosis alone and those with extensive lytic lesions had intermediate survivals of 32 per cent and 33 per cent respectively. Of the other major prognostic features only anaemia demonstrated a significant correlation with X-ray findings in terms of survival (p less than 0.001) suggesting that those with normal X-rays may have a more diffuse marrow involvement accounting for their poor prognosis. The response on bone X-rays in 102 patients who completed nine cycles of chemotherapy was also analysed. Patients with evidence of healing had a 3-year actuarial survival of 37 per cent, those with progression 36 per cent and those with stable X-rays 65 per cent (p less than 0.01). Normal bone X-rays at presentation and radiological evidence of healing following therapy appear to be bad prognostic signs in multiple myeloma.