Thin films of CdO have been deposited using a spray pyrolysis process and the physical properties investigated for the layers deposited using different substrate temperatures. The techniques used to investigate the layers include X-ray diffractometry, scanning electron microscopy, transmittance and reflectance vs. wavelength measurements, and Van der Pauw measurements. Single-phase layers of CdO were produced for substrate temperatures > 175 degreesC, but the most transmissive layers with the lowest values of resistivity were obtained for layers grown at 200 degreesC. The high figure of merit of these layers (1.02 X 10(2) Omega(-1)) means that they could find application in large-area electronic devices.