Abstract: Disclosed is a method and system for inverse planning of radiosurgery of tumors. Isocenter points are replaced systematically throughout a model of a tumor to generate a sequence of simulated radiation beams. This crossing geometry and intersection pattern of these beams is then computed. Through fine tuning of certain variables used in the calculations in accordance with the present invention, radiosurgery is planned in a manner which avoids over irradiation of healthy tissue and critical regions, and allows for homogeneity of dose inside the tumor. The method of the present invention allows for exact decision about the feasibility of use-defined dose distributions.