Understanding thermal degradation is key to polymer processing, especially in the synthesis of fire-safe polymeric materials. Along with introducing readers to thermal degradation techniques such as thermogravimetry and matrix-assisted laser desorption/ionization mass spectrometry, this guide describes making predictions over the lifetime of the product and gives typical thermal degradation pathways. It also gives the kinetics of thermal degradation and special considerations to take in the case of copolymers and blends, styrene polymers and other types such as natural polymers and polyesters, reinforced polymer nanocomposites, and temperature- resistant and inorganic polymers. It describes recycling of polymers by thermal degradation, thermal degradation during the processing of polymers, and modeling processes.