Abstract Evidence-based practical guidelines on diagnosis, prognosis, and treatment on the most frequent adult brain tumours are delineated. In Europe, 27,000 new cases of malignant glial tumours and 1000 new cases of malignant ependymal tumours are diagnosed every year. The most common glial tumours are glioblastoma multiforme and anaplastic glioma, comprising more than 50% and 10%, respectively, of the total gliomas. Prognosis of gliomas is generally poor. Environmental and genetic factors have been correlated with an increased risk of developing brain tumours. Surgical resection represents the first treatment option for all histotypes. Role and timing of radiotherapy and chemotherapy as well as treatment for recurrent/progressive disease should be based on age, performance status, histopathological diagnosis, molecular markers, and previous therapy. Impaired neurocognitive and neuropsychological function is common in long-term survivors, regardless of the histology and grade of the tumour and should be taken into account in treatment planning.