When compiling the present atlas our aim has been to provide the practis­ ing radiotherapist with a handbook which would help him to plan the radiation therapy of tumours of individual organs. Apart from a few ex­ ceptions, all isodose charts in this atlas show dose distributions resulting from external irradiation. Combination of external irradiation with intra­ cavitary radium therapy is presented in the treatment of carcinoma of the uterine cervix, in which case the two techniques are complementary. Thd immense material of the pertinent literature could, naturally, not have been included in the atlas. As a result of scrupulous selection, the isod-.:se charts shown may not invariably be the optimum ones, and some of them may not be the most modern. However, the usefulness of the information they provide has made us to keep them all the same. We did not intend to change the original charts in any way and stan­ dardization of the isodoses was not undertaken. Radiation parameters are given in the figure captions and, if available, information has also been provided on the phantoms used by the authors. Naturally, the isodoses presented will not automatically apply to all situ­ ations and all apparatuses without due attention to the individual patient ::Jnd technical details such as penumbra and source diameter. They merely serve as a starting point and will help to save time and work during treatment planning also with the computer.