The interaction between thin films of ethylenedioxythiophene (EDOT) and polycrystalline copper and gold surfaces has been studied using photoelectron spectroscopy. Thick films of EDOT (∼100 Å) have been prepared by vapor deposition onto clean gold surfaces, which were cooled down to a temperature of 170 K during the deposition process. Monolayers were prepared by slowly heating the thick films up to 300 K. At 300 K most of the material has evaporated from the surface and about one monolayer remains chemisorbed on the gold surface. This shows that there is an interaction between EDOT and Au. This chemisorption causes a shift of around -0.5 eV of the binding energies for the core level electrons, presumably because of screening of the core-hole by the metal. An experimental and theoretical analysis of the valence level electrons suggests that two molecular orbitals, localized at the thiophene part of the molecule, are involved in the interaction with the metal atoms of the surface. The most likely orientation of the EDOT molecules is parallel to the Au surface. Upon adsorption the work function is changed from 5.2 eV for the clean gold surface to 4.0 eV for the EDOT monolayer. In the case of EDOT adsorbed on clean copper surfaces, no interaction was observed.