Magnetic resonance spectroscopy (MRS) is a modality available on most clinical MR scanners and readily integrated with standard MR imaging (MRI). For the brain in particular, MRS has been a powerful research tool providing additional clinically relevant information for several disease families such as brain tumors, metabolic disorders, and systemic diseases. The most widely-available MRS method, proton ( H; hydrogen) spectroscopy, is FDA approved for general use in the US and can be ordered by clinicians for patient studies if indicated.