Alterations in neuro-chemical abundance may serve as biomarkers of malignancy in brain tumors. Proton magnetic resonance spectroscopy (MRS) provides an effective tool for monitoring the metabolic changes noninvasively. While the metabolic alterations reported thus far (e.g., choline, lactate, lipids, and N-acetylaspartate) may be effective at identifying tumor tissue, they are not tumor specific. Furthermore, the diagnostic/prognostic capability of these metabolites is controversial. The discovery of the production of 2-hydroxyglutarate (2HG) in gliomas with mutations in isocitrate dehydrogenase (IDH) 1 and 2 (Dang et al. Nature 2009) has created the central interest among the basic and clinical scientists. We developed an MRS protocol that can provide in-vivo detection of 2HG in IDH-mutated gliomas (Choi et al. Nat Med 2012). Beyond this simple detection of 2HG, we investigated the clinical utility of 2HG. The results showed that 2HG has the great potential for noninvasive monitoring of tumor stableness, progression, and response to treatment in IDH mutated gliomas. The MRS protocol can also provide reliable measurement of glycine, which is known to be a biomarker for malignancy in brain tumors. MRS data from a longitudinal study in glioma patients, obtained over the past 4 years, will be presented with the focus on 2HG and glycine, together with some technical considerations of in-vivo MRS.