Careful diagnostic and early therapy are especially important in cases of scaphoid fractures. This is due to the patients being mostly young and the high number of non-unions of these carpal bones. Conservative and various operative treatments are therapeutical options. Out of the patients who underwent surgery from January 1993 to February 1999 42 patients with a scaphoid fracture and 88 patients with a scaphoid non-union were, in addition to standard X-ray examination, examined clinically and by MRI pre- and post-operatively. Fractures of the scaphoid were treated by Herbert screw fixtion. The operative treatment of non-unions of the scaphoid included the transplantation of an iliac crest graft and Herbert screw fixation. Post-operatively a cast-immobilisation was done. Subjective statements of the patients and clinical results were assessed. The classification of Herbert and Fisher (1984)/Filan and Herbert (1996) for X-rays was used. The signal intensities of the MRI in the fragments of the scaphoid were determined qualitatively and quantitatively by computer calculation, comparing the pre- and post-operative results with one another. Post-operative results of the scaphoid fractures were in most cases good and excellent. 67 patients with a scaphoid non-union and 11 with a scaphoid fracture showed a pre-operative diminishing of the signal in the proximal fragment. For these patients, the fusion rate was lower than in patients without pre-operative signal reduction. The examination shows that in most cases bony fusions with good clinical results could be achieved by Herbert screw fixation. The MRI seems to be able to complete the radiological classification of the fractures regarding a prognosis.