Pyrolysis gas chromatography mass spectrometry (Py/GC/MS) is an instrumental method that enables a reproducible characterisation of the intractable and involatile macromolecular complexes found in virtually all materials in the natural environment. It differs from GC/MS in the type of sample analysed and the method by which it is introduced to the GC/MS system. Instead of the direct injection of a highly refined organic solution, a few mg (or in the case of materials with a high organic carbon content,