An attempt was made to investigate the possibility of applying thermally stimulated depolarization current (TSDC) techniques to the analysis of multi-component glasses with different relaxation mechanisms. Therefore, multi-component borosilicate glass containing the addition of Li2O, Na2O, MgO, BaO or in some cases Fe7O3, was investigated by integral and by partial TSDC measurements. Except for the usual partial peaks, which follow the applied poling window DeltaT(p), some additional peaks appeared independently of DeltaT(p). By the consideration of temperature of the partial peaks maxima versus temperature of poling it was possible to map and separate different and overlapping events. Generally, in the range 170-320 K several processes were observed. P-0 with maximum at 198 2 K caused by the space charge, P-1, at 228 +/- 3 K and P-2 at 263 +/- 4 K caused by dipolar relaxations. The windowing technique shows a higher temperature process P-3 at about 285-330 K attributed to the Maxwell-Wagner effect. Special attention was paid to the appearance of a number of single-relaxation time processes in the range of P-2 caused by the interaction between the divalent ions and vacancies. Glass with Fe(2)0(3) showed a decrease in the distribution width in P-1 and P-2 ranges, which corresponds to an increase in the homogeneity of the system. The addition of Fe(2)0(3) also increased the magnitude of the depolarized current. An additional heat treatment of the glass increased the number of the single-relaxation time processes. (C) 2004 Elsevier B.V. All rights reserved.