The growing importance of local sulfonamide therapy in dermatology (1, 2, 3, 4) and the relative paucity of literature dealing with the effects of ointment bases on skin bacteria has prompted the present investigation. The latter problem was partially studied by Pillsbury, Livingood and Nichols (5) in a previous report. These workers used the method of Price (6) as modified by Pohle and Stuart (7) in determining the effect of various cutaneous applications in changing the rate at which bacteria were removed from the skin during a standard scrubbing technic. They found, in brief, that certain ointments, when applied to the skin for periods varying between several minutes and one hour, resulted in a rise in bacteria recovered as compared to scrubbing experiments where no applications were used. The ointments used included petrolatum, lanolin, 3% and 5% ammoniated mercury in ointment, IJ.S.P., 3% and 5% ammoniated mercury in an emulsion type base, phenylmercuric nitrate (1:1,500) in an emulsion type base, and lastly ointment U.S.P. Similar effects were noted with distilled water, 0.02% aqueous solution of potassium permanganate, 0.1% aerosol in water, 0.5% aqueous solution of aluminum acetate and the simple wearing of rubber gloves. A suggestion was made that this rise in bacterial count might be due to the softening action of the various applications allowing better removal of bacteria, surface debris and superficial stratum corneum. The opposite action was observed following the local use of 70% ethyl alcohol and Castellani's Carbolfuchsin paint. Of interest, in connection with these findings, is a study by Cromwell and Leffler (8) using a technic similar to the above workers. They found that astringent substances (ethyl alcohol and potassium alum) have a hardening action on the epidermis and, thereby, prevent bacteria from being scrubbed off the skin. By contrast, other substances (sodium sulphide and ammonium suiphide) which tend to soften the epidermis result in a rise in bacterial count.