The combination of elemental analysis (EA) with isotope ratio mass spectrometry (IRMS) has allowed the explosion of stable isotope analysis across a broad range of application areas. It is an established technique for the analysis of bulk materials such as organic mixtures, soils, fluids, and inorganic minerals. Thanks to the relatively simple operation of the system and the broad range of applications covered, EA-IRMS has become the primary mode of stable isotope ratio analysis in many laboratories. In EA-IRMS, the elemental analyzer combusts the solid or liquid sample via high-temperature combustion or pyrolysis to gaseous products before passing to the isotope ratio mass spectrometer for the determination of its isotopic composition.