43 patients suspected clinically of having tumours of the adnexa were examined by MR and 40 by endosonography in a prospective study. All underwent surgery. Correct lateralisation of the tumour was achieved by MR in 39 out of 43 cases (91%) and by endosonography in 32 out of 40 cases (80%). By means of MR it was possible to recognise the affected organ in 79%, and by vaginal sonography in 70% of women. Prediction of malignancy was possible with MR in 39 out of 43 cases (91%) and by endosonography in 30 out of 40 cases (75%). Infiltration into the omentum and gut and peritoneal metastases was missed by both methods (4 out of 4 cases).