Conventional external beam radiotherapy has been historically employed in the treatment of pituitary adenomas either as a single modality or following suboptimal surgical resection. However, with the widespread adoption of the trans-sphenoidal surgery, the role of radiation therapy has been limited to cases deemed resectable or in those with subtotal resections. Advances in radiotherapy have improved the dose distribution to the pituitary mass while minimizing the volume of normal tissues receiving doses of radiation near or exceeding their inherent tolerances, permitting radiation oncologists to migrate from simple 2D radiation planning to 3D planning. Fractionated radiosurgery, linear-accelerator/gamma source-based radiosurgery, or image-guided/intensity-modulated radiotherapy is now commonly employed. Long-term follow-up data demonstrate excellent progression-free survival and local control along with few complications for all radiation treatment modalities whether employed as monotherapy or following subtotal resection.