From 1979-89, 211 women with cancer mammae were irradiated at the Norwegian Radium Hospital after breast-conserving surgery performed at different hospitals in Norway. 181 of these patients were called in for re-examination to check the procedures for treatment and the cosmetic results. Only 37% of the patients had undergone mammography prior to surgery and 48% of the patients had had two or more operations before the irradiation. The cosmetic results were not very satisfactory in 45% of the patients. Reduced cosmesis was mainly due to less than optimal surgery. We propose better standardisation of the treatment programme for breast preservation. Optimal results require close collaboration between radiologists, surgeons, oncologists and pathologists. The treatment must be organized in a way that facilitates this collaboration.