Silver-cobalt-phosphate glasses of (50-x) Ag2O-50P(2)O(5)-xCoCl(2) composition with x varying between 0 and 15 mol% were prepared by a melt quenching technique. These glasses were characterized by X-ray diffraction, Fourier transform infrared spectroscopy and differential scanning calorimetric techniques. Their thermal (T-g, and T-c) and electrical properties (ionic transference number and electrical conductivity) have been investigated. Infrared spectral studies indicate the formation of P-O-Co bonds in these glasses that replace P-O-center dot center dot center dot Ag+ bonds. The results of thermal studies are in accordance with the FT-IR findings and support the formation of P-O-Co bonds. The T. and Tc values were found to increase with increasing amount Of CoCl2 indicating increased cross-link density and enhanced chemical durability of the synthesized glasses. Transference number measurements show that these glasses are essentially ionic conductors. The electrical conductivity (sigma) of silver-phosphate glasses doped with 5 mol% CoCl2 is found to be the maximum. The sigma values obtained for different compositions of the dopant CoCl2 have been correlated with the structural changes in the silver-phosphate glass matrix. (C) 2008 Elsevier B.V. All rights reserved.