The thermoanalytical approach to the study of the kinetic lability of coordination and inclusion compounds in the reversible processes of thermal dissociation is discussed. The secondary crystal structure that existed initially and its transformation into the reaction zone on the surface of the grain are considered. It is pointed out that in any experiment the measured decomposition rate is averaged over ail crystal faces. Kinetic data can be interpreted in terms of the transformation mechanism only for a series of isostructural compounds. The author's own experimental data on thermal dissociation processes for coordination and inclusion compounds are presented and considered.