The results of a study on the percutaneous absorption of two corticosteroids, Halcinonide at 0.1% and Triamcinolone acetonide at 0.1%, employing an original thermographic method, are reported. In a first group of subjects treated with one application of the two corticosteroids a stronger activity of the Halcinonide was found than in a second group of subjects, after repeated applications, resulting progressively more evident and of longer duration in comparison with Triamcinolone.