Organic acidurias are an important group of inherited metabolic disorders that affect the intermediary metabolic pathways of carbohydrate, amino acid, and fatty acid oxidation, leading to the accumulation of organic acids.(1) The 2-hydroxyglutaric acidurias are rare neurometabolic disorders characterized by developmental delay with or without other neurologic dysfunction. Three different subtypes have been described: d-2-hydroxyglutaric aciduria, l-2-hydroxyglutaric aciduria, and combined d-l-2-hydroxyglutaric aciduria. We describe the case of a child presenting with developmental delay who was found to have the classical biochemical, imaging, and genetic features of l-2-hydroxyglutaric aciduria.