The possible use of polymeric materials in thin-film solid electrolytes for battery systems, fuel cells, sensors and other electrochemical applications has stimulated worldwide interest in metal salt solvating macromolecules. Polymer electrolyte membranes comprising of poly(methyl methacrylate) (PMMA), poly(vinylidene fluoride) (PVdF) and lithium perchlorate are prepared using a solvent casting technique. Polymer blends have been characterised by FTIR and XRD studies to determine the molecular environment for the conducting ions. The role of interaction between polymer hosts on conductivity is discussed using the results of ac impedance studies. The ionic conductivity is presented as a function of temperature and PVdF content. Room temperature conductivity of 3.14 X 10(-5) S cm(-1) has been obtained for the [0.25PMMA/0.75PVdF]-LiClO4 polymer complex.