Despite the best efforts of researchers to try to understand spontaneous combustion it still affects many mines. Laboratory testing and modelling have been available for many years and yet they are still not able to reliably predict the propensity for a coal seam to spontaneously combust. The complexities of the spontaneous combustion process are explored by delving into the chemistry of the oxidation process. It is able to demonstrate why the testing and modelling of spontaneous combustion can be of limited accuracy. Laboratory tests and simulations are carried out under conditions cannot reflect the full complexity of the underground environment. This does not mean that the experimental work is meaningless, but the results need to be included as part of a proper risk assessment that includes the contributions and influences of other parameters currently not able to be adequately modelled or simulated in the laboratory. In addition laboratory testing can offer insights into the influence of such things as water content, ash content and particle size. It is recommended that the Trigger Action Response Plans (TARP) in place in underground coal mines go beyond detection of spontaneous combustion and include indicators that identify the increased likelihood of spontaneous combustion and allow for controls to be put in place in time to prevent spontaneous combustion from occurring.