Despite multimodal treatment with surgery, radiotherapy and chemotherapy, glioblastoma is an incurable disease with a poor prognosis. During the disease course, glioblastoma patients may experience progressive neurological deficits, symptoms of increased intracranial pressure such as drowsiness and headache, incontinence, seizures and progressive cognitive dysfunction. These patients not only have cancer, but also a progressive brain disease. This may seriously interfere with their ability to make their own decisions regarding treatment. It is therefore warranted to involve glioblastoma patients early in the disease trajectory in treatment decision-making on their future care, including the end of life (EOL) care, which can be achieved with Advance Care Planning (ACP). Although ACP, by definition, aims at timely involvement of patients and proxies in decision-making on future care, the optimal moment to initiate ACP discussions in the disease trajectory of glioblastoma patients remains controversial. Moreover, the disease-specific content of these ACP discussions needs to be established. In this article, we will first describe the history of patient participation in treatment decision-making, including the shift towards ACP. Secondly, we will describe the possible role of ACP for glioblastoma patients, with the specific aim of treatment of disease-specific symptoms such as somnolence and dysphagia, epileptic seizures, headache, and personality changes, agitation and delirium in the EOL phase, and the importance of timing of ACP discussions in this patient population.