Modern radiotherapy improves the local control of the tumor through a better target volume definition while avoiding excessive irradiation of organs at risk keeping normal function of organs for a better patients' quality of life. These outcomes concern radiotherapy used as a radical treatment, associated to surgery either before the removal of the tumor like in rectal carcinoma or after complete surgical excision of breast cancer or tumor located in the head and neck area. Treatment of locally advanced diseases is delivered with combined modality treatment including conventional chemotherapy. At present many clinical researches are conducted with targeted therapies, improving radiation effect at the tumor level. The technological improvements are introducing stereotactic treatments, for lung carcinoma and liver tumors not amenable to curative approaches by surgery.