Diffusion of evaporated gold arid silver into Bisphenol A polycarbonate has been studied using the radiotracer technique in combination with ion beam sputtering for serial sectioning. Diffusion coefficients between 4 x 10(-14) and 1 x 10(-16) cm(2) s(-1) were measured in the temperature range between 210 and 130 degrees C. The metal concentration in the polymer turned out to depend strongly on the evaporation rate. An Arrhenius-like temperature dependence with activation energies of 1.02 eV for silver and 1.13 eV for gold was found. The low diffusivities, which are not affected by the polymer dynamics, are interpreted within molecular theories for diffusion of gases in polymers with an additional attractive interaction between metal atoms and polymer chains.