Damage to the central nervous system induced by treatment of brain tumors is common and impairs the patient quality-of-life. Neurotoxicity is induced by synergistic effects of different cytotoxic treatments such as radiotherapy and chemotherapies administered concurrently or sequentially. Recent progress in the management of brain tumors has led to new neurotoxicities. The growing concern about the neuropsychological performance of patients has disclosed another type of brain damage which has been largely neglected to date. Neurological toxicity can be acute, requiring dose adaptation or a change of drugs. But it also often occurs late and can be irreversible. To date, treatments have been ineffective. The early diagnosis of neurotoxicity is thus a major challenge. Numerous clinical studies suggest an individual sensitivity which is not only related to age or vascular status, but also to genetic predisposition that remains to be detailed. Understanding the mechanisms of personal susceptibilities would be helpful in designing more tailored treatments. In this review we address the question of adverse effects of brain radiation as well as those of chemotherapy protocols which are particularly toxic for the central nervous system that is, methotrexate, platin and aracytin.