The variation of the d.c. electrical conductivity, sigma, with composition and temperature was investigated for glasses of the Ge-In-Se system. The results indicate a decrease in the activation energy for electrical conductivity, DELTAE, and an increase in sigma on introduction of indium into Ge-Se glasses. The changes in DELTAE and sigma with composition (selenium content in the glasses) are identical for the Ge(x) In5 Se95-x and Ge(x) In8Se92-x families. The results have been traced to the conduction controlled by charged defects in these chalcogenide glasses. The changes in DELTAE and sigma have been explained by a shift in the Fermi level, being brought by the introduction of indium.