In this paper we report the results of investigations carried out on the electrical properties of silver-island films deposited onto polymethylmethacrylate-coated substrates heated to 423 K, well above the softening temperature of the polymer. For films with initial resistances less than 4.1 M/-, a sharp fall in resistance was observed which may be due to the formation of a close-packed subsurface structure. This fall in resistance occurred after a time interval of 180 s following deposition. For films with initial resistance greater than 4.1 M/-, the resistance increased enormously, marking this resistance range as a possible transition region. A film deposited at room temperature and heated behaved similarly to the silver-island films on glass substrates.