This chapter contains sections titled: Introduction MR Properties of 19F In Vivo Applications of In Vivo Fluorine MR in Medicine and Drug Development Fluorine MR Spectroscopy in Cancer: Fluoropyrimidines Fluorine MR Spectroscopy in Neuropharmacology Fluorine MR Spectroscopy for Measuring Biodistribution Analysis of In Vivo 19F MR Spectra Conclusions and Perspectives Acknowledgments Abbreviations References