Polyimides can be infused with silver complexes by the use of supercritical fluids. Highly reflective polyimide films were formed by infusing (1,5-cyclooctadiene-1,1,1,5,5,5-hexafluoroacetylacetonato)silver(I) [Ag(COD) (HFA)] into a number of polyimides and then thermally curing those films at 300 °C for time intervals between 30 min and 3 h. Reflectivities of the films exhibited strong dependence on the infusion and cure conditions as well as on the type of polyimide used. The highest reflectivity of 67.1% was achieved with a silvered film prepared from 3,3′,4,4′-benzophenonetetracarboxylic acid dianhydride (BTDA) and oxydianiline (ODA) infused at 5000 psi, 100 °C, for 30 min and cured for 1 h at 300 °C. Reflectivities of silvered surfaces of other polyimides investigated varied from 39% to 61%. A strong correlation between the presence of a ketonic group in the polyimide structure and the formation of mirror surfaces was detected.