The HPLC-MS technique is a modern and effective method for achieving a comprehensive analysis of elutable components (extractables) from polymer materials. Applied correctly, it is superior to the classic HPLC-UV method and ideally complements the GC-MS method for the identification of thermally unstable, reactive and high-molecular analytes (molecular masses of about 100-4000 g/ mol). The HPLC-MS method does require fundamental and wide-ranging work to optimize the liquid chromatographical separation system and the ionization conditions of the mass selective detection for an effective use of the ion trap method. The ion trap method gives the possibility of forming MS/MS spectra with relatively high fragmentation from certain analytes. The MS/MS-technology requires the development of parameter specific libraries of spectra.