Objective-To explore the experiences patients and relatives after the diagnosis treatment of malignant cerebral glioma. Design-Two year prospective study with home interviews, Setting-Six neurosurgery and radiotherapy centres in London, Subjects-75 patients and 66 close relatives interviewed at diagnosis, 58 patients interviewed after radiotherapy, and 27 interviewed after recurrence, Main outcome measures-Awareness of likely prognosis, distress, dissatisfaction with radiotherapy and perception of severe problems in everyday life, Results-As they began radiotherapy most patients understood that they suffered from a brain tumour (95%; 71/75), but only one quarter (19/75) seemed fully aware of the poor prognosis. Others were unaware (43%; 32/75) or only partly aware (32%; 24/75), The more aware patients were more distressed. Relatives were three times more Likely to be aware of the prognosis (67%; 44/66) and were more distressed, Although 39% (29/75) of patients initially made negative comments about radiotherapy, only 17% (13/75) were completely dissatisfied, The decision to accept radiotherapy could be discussed directly with 19 fully aware patients, Twelve found radiotherapy acceptable if it were medically advised or if it improved survival. Assessed by their own reports of problems only 40% of patients achieved a period of stability or remission, yet dissatisfaction with treatment did not increase. Conclusion-Most patients with malignant glioma initially seemed unaware or only partly aware of the poor prognosis. Relatives were more aware, more distressed, and often concerned to protect patients from full awareness, which made it difficult to explore with patients directly the possible trade off between quality and length of life, Conceptualising the question as a rational choice ignores the social and emotional context of life threatening disease.