Watchful waiting has long been justified in the Netherlands for patients in whom a low-grade glioma is suspected. According to recent advances in knowledge it is clear that the course of a suspected low-grade glioma cannot be reliably determined by clinical characteristics, imaging or biopsy. Early resection of the tumour provides a histological diagnosis, the possibility of removing a source of epilepsy and postponement of tumour growth and progression. Alleviation of symptoms, sustained quality of life and cognition are at least as important an aim of treatment as survival and postponement of tumour progression. In our opinion, early resection should be strongly considered in every patient with a suspected low-grade glioma. However, radiotherapy or chemotherapy should only be considered early in the presence of unfavourable prognostic factors or persistent epilepsy. Each patient in whom a low-grade glioma is suspected should receive specific treatment advice from a neuro-oncological team.