The surface of a polycrystalline Ni/Cr alloy has been examined using Auger electron spectroscopy (AES), ion scattering spectroscopy (ISS) and X-ray photoelectron spectroscopy (XPS) before and after a 1 h, 400 degrees C anneal in air. The use of these three techniques provides depth-sensitive information as a result of their different sampling depths. The outermost surface layer contains mostly O and some Ni, and the near-surface region consists primarily of NiO. Using sputter depth profiling coupled with AES and XPS, a Cr-rich region is observed between 130 and 175 min of sputtering which consists of two layers. The upper portion of this region contains Ni and Cr metals as well as a mixture of CrO and Cr2O3. The lower portion of this region contains a larger Cr oxide concentration compared with the upper layer, and the Cr oxide consists mostly of CrO and CrO3. Below this region only Ni metal, Cr metal, and a small amount of Cr oxide species are present. The Cr-oxide-rich layer may be responsible for the passivation of Ni/Cr surfaces toward oxidation.