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On the basis of the results obtained for eutectic Te--Ge glass, the application of the simple Piloyan method for study of the energetics of the glass-to-crystal transition was considered. Some new applications of this method to not yet completed transitions were proposed. Limitations of the method and factors exerting an effect on the calculated activation energies were discussed. Piloyan's procedure was compared with Kissinger's method.The simplest way of determining the activation energy of a solid-state transition seems to be that suggested by Piloyan et al. [1 ]. It requires only one DTA experiment, at an arbitrarily chosen heating rate (within the range 10-40 deg/min).The basic assumption is that the deviation from the baseline, AT, is proportional to the reaction rate d~/dt, independently of the fraction reacted, within the c~ range 0.05-0.8 (c~ is the extent of reaction). This assumption holds true for zero-order reactions [2].In the original paper [1] the authors mentioned, in support of their method, reactions of dissociation (CaCOa, MgCO3) and dehydration (CuSO~.5 H20, CaC20~.H20 ). In the present work, the suitability of this method for the study of the energetics of a glass-to-crystal transition was considered. Our own earlier data obtained for eutectic Te-Ge glass [3] were re-calculated in order to assess Piloyan's method. Activation energies E given in [3] have been determined according to Kissinger [4].In the system studied, the glass-to-crystal transition comprises two stages with different mechanisms. Only the first stage is controlled by a diffusional mechanism [3], and that is why the results concerning this stage were taken into further consideration. In Table 1 the experimental data are presented, together with the estimated values of E. The function log I vs. 1/T is plotted in Fig. 1. The results permit the conclusion that, for estimation of E, it suffices to use only one DSCtrace taken at arbitrarily chosen parameters. The error is below 10~. However, some precautions should be taken: -independently of the shape of the peak, at least four points are needed (n > 4); -temperature range AT (about 3-10 deg) should correspond to about the half-height of the peak (Fig. 2);