NMR spectroscopy being a primary ratio method of measurement is highly suitable to evaluate the quality of drugs. NMR spectroscopy can be used for the identification of a drug substance, the identification and quantification of impurities arising from the synthesis pathway and degradation, or residual solvents as well as the determination of the content in the assay. This review gives an overview of the application of quantitative NMR spectroscopy in International Pharmacopoeias and for licensing purposes.