The thermoelectric power, S, of a number of palladium and platinum alloys has been measured in the temperature range 2°K to 120°K. For alloys of palladium or platinum with theirneighbouringelements it has been possible to correlate the sign of the diffusion component of thermopower Sdin the residual resistance temperature range with the slope of the density of states versus concentration curves. Furthermore, there is excellent numerical agreement between the observed values of Sd/T and those calculated by a method based on the rigid band model for all the platinum-gold alloys investigated and for the palladium-silver alloys apart from one which contained less than 1 % silver. However, the sign of Sdwas not predicted correctly for a palladium-platinum alloy. Each of the specimens exhibits a large positive phonon drag component of thermopower which persists to high temperatures and is not greatly reduced on alloying. These two features as well as the positive sign are the result of phonon-induced scattering by either s-d or d-d processes.