Gamma Knife radiosurgery can be used as an alternative or complementary therapy to neurosurgery or radiotherapy for the treatment of some brain disorders or tumors of small volume. The most frequent indications are brain metastases, vestibular schwannomas, meningiomas, trigeminal neuralgia, arteriovenous malformations, some gliomas, and pituitary adenomas. Created in 1999, the Gamma Knife Center of the ULB remains currently the unique center in Belgium where a Gamma Knife radiosurgery treatment can be performed.