Radiation therapy, alone or in combination with chemotherapy, is the most effective treatment for certain types of brain tumors. Radiation oncologist Kathryn Beal of Memorial Sloan-Kettering Cancer Center discusses the latest techniques — including stereotactic radiosurgery, intensity-modulated radiation therapy (IMRT), and image-guided radiation therapy (IGRT) — to deliver high doses of radiation directly to a tumor while sparing healthy brain tissue.