A program for a personal computer has been developed to calculate and optimize dose distributions around a high dose intracavitary afterloading applicator having a single source. The problems of the local irradiation of the endometrium-carcinoma are emphasized in connection with the optimization criteria for an adequate irradiation planing. Exemplarily, the anisotropic proportions of absorption around a special type of applicator are calculated. In addition, an algorithm for optimization of dwell times of three-dimensional arranged source positions according to a prescribed dose distribution is theoretically presented. Further, an easy way of finding isodosis by given source positions and dwell times is introduced by taking into consideration the need to superimpose the dose distribution with external radiation fields. All calculations are tested in a water phantom.