|The discovery of the production of 2-hydroxyglutarate (2HG) in gliomas with mutations in isocitrate dehydrogenase (IDH) 1 and 2 has created great excitement among basic scientists and neuro-oncologists. Although the role of 2HG is well established for diagnosis and prognosis, how it can be used for improving patient care is largely unknown. Here we present in-vivo 1H MR spectroscopy data from >100 glioma patients and discuss the clinical utility of 2HG. The data indicate that 2HG is a sensitive biomarker for monitoring tumor stableness, progression, and response to treatment in IDH-mutated gliomas. Noninvasive analysis of 2HG by MRS may have the great potential for developing methods for therapeutic benefit.