Mass spectrometric analysis of the volatiles evolved from a pyrolysed polymer system has been utilised in two areas. First, pulse laser heating can generate conditions analogous to the pyrolysis conditions which occur behind the flame front in a real fire and thus provides an experimental system which can be utilised to investigate the behaviour of flame retardant plastic systems under such conditions. The temporal evolution of benzene from several different plasticised PVC samples is reported and discussed. Secondly, pyrolysis/mass spectrometry (Py/MS) coupled with pattern recognition analysis (PRA) has been successfully used to differentiate between different polymer types (e.g. polystyrene, polypropylene) and structurally similar polyacrylics. However, the technique could not differentiate between a range of commercial polypropylene samples from different sources. An alternative approach, thermal desorption—gas chromatography J mass spectrometry (TD—GC/MS), which enables analysis of volatiles evolved below the pyrolysis temperature, successfully differentiated between the polypropylene samples. These observations are interpreted as indicating that Py/MS yields information based on structural differences in the polymer chain, whereas TD—GC/MS is more able to provide information based on the analysis of residual volatiles and additives that are evolved below the pyrolysis temperature.