The current status of clinical Magnetic Resonance Spectroscopy (MRS) will be reviewed. Applications to brain, heart and skeletal muscle will be illustrated. By providing non-invasively detailed information on the biochemical processes taking place in living tissues, MRS, as a molecular imaging method, has significantly contributed to advancing scientific knowledge of the metabolic underpinnings of a number of pathologies. It also plays a role in the quantitative assessment of various therapeutic interventions (clinical trials). In most cases, clinical MRS exploration on humans has to be performed in conjunction with other MR modalities (the "multimodal MR approach") in order to provide useful pronostic and diagnostic information. MRS real impact and added value in advancing human health will be discussed.