Conventional radiotherapy (RT) in breast cancer treatment includes a total dose of 50Gy with a 16Gy-boost in a smaller volume. After mastectomy, radiotherapy of all node-positive patients seems to be applied whatever the positive node number. Modulation of RT technique uses the fraction dose, namely through accelerated hypofractionation regimen in a constant volume. A group of patient with a low risk of recurrence may benefit from this technique. In a smaller irradiated volume, accelerated hypofractionation still belongs to intensive clinical research evaluating intraoperative RT, brachytherapy, Mammosite, and external partial breast irradiation. Intensity-modulated radiotherapy decreases the risk of moist desquamation. The development of the gating offers greater protection of certain critical organs including lung, heart, and chest/ribs. Finally, predictive tests identifying patients at high risk of developing late effects led us to adapt RT technique to some of them and therefore increase long term therapeutic ratio.