The crossing-point temperature (CPT) method for measuring ignition kinetics of particulate combustible solids was introduced in 1995 by Chen and Chong. The method has since been successfully applied to milk powders and wood sawdust by the same authors. There is a potential for more extensive application of the technique because it significantly reduces the expense in terms of time and effort in measuring the kinetics, in comparison with the traditional basket heating method. However, there are still some fundamental issues which need to be addressed. This paper discusses the following issues: The reason why only two temperatures are sufficient in determining the heat conduction term to be negligible; Extension of the slab analysis to other symmetrical bodies; ＇Uniqueness＇ of the crossing-point temperature; The case in which heat capacity is temperature dependent.