This paper describes the oxidation of a base-line Fe-8Cr-16Ni (weight percent) composition, compared to that of alloys with small additions of Al, Si, Mo, and Mn. Oxidation was done in air over the temperature range of 600 deg-1000 deg C for up to 1000h. Alloys that contained Al and Si showed excellent oxidation resistance because of the formation of a layer containing Si at the scale-metal interface. Small additions of Al seemed to form oxide nuclei during a transient oxidation period, aided the formation of a layer containing Si and/or a chromium oxide, and provided better oxide adherence. Molybdenum and manganese additions stabilized a fully austenitic microstructure at room temperature. The oxidation behavior of these alloys was compared to that of 304 stainless steel and some commercial superalloys. Reaction kinetics, oxide morphologies, and oxidation mechanisms of the substitute alloys are described.