Glioblastoma (GBM) is the most lethal form of brain tumor and remains a large, unmet medical need. This review focuses on recent advances in the neurosciences that converge with the broader field of immuno-oncology. Recent findings in neuroanatomy provide a basis for new approaches of cellular therapies for tumors that involve the CNS. The ultimate success of immunotherapy in the CNS will require improved imaging technologies and methods for analysis of the tumor microenvironment in patients with GBM. It is likely that combinatorial approaches with targeted immunotherapies will be required to exploit the vulnerabilities of GBM and other brain tumors.