The influence of anodic films up to 3000Aå thick on the subsequent high‐ temperature oxidation characteristics of tantalum was studied. At a given temperature, the anodic films decreased the gross oxygen consumption rate to an extent dependent on their thickness and also delayed the onset of the “breakaway” increase in the oxidation rate common to this metal. The result that very thin anodic films pass comparatively large quantities of oxygen to the metal while postponing the appearance of the crystalline oxide phases permitted some oxygen solution effects during the early stages of oxidation to be observed.