In 1003 patients with a total of 2467 clinically or scintigraphically suspect skeletal parts, conventional x-ray examination at the time of first study resulted in 95% of cases (2331 skeletal parts) in a correct diagnosis. Computed tomography permitted an exact diagnosis in 52% of roentgenologically equivocal findings (136 skeletal parts). In 40% of these patients even by computed tomography metastasis was only suspected, in 8% there were unspecific findings, while by follow-up bone metastasis was proven. In 64.8% of the whole patient collective there were metastatic destructions and in 32.6% of patients benign lesions were found. Superiority of CT compared to conventional x-ray diagnosis resulted from exact demonstration of the intra- and extraosseous extent of lesions and the possibility of density measurements. It depended mainly upon the localisation of the pathologic process.