The initial stage of formation of the Ni/A12O3 interface under different conditions was studied by various surface science techniques. Nickel was deposited in situ in a UHV system onto the basal plane of a sapphire substrate at various temperatures and oxygen partial pressures. The interfacial reaction processes were simultaneously monitored by XPS. When Ni was deposited at elevated temperatures and in the presence of sufficient oxygen, the NiAl204 spinel was formed epitaxially on the Al2O3 substrate, as confirmed by LEED. While under UHV conditions (<4×10−11 torr) and at elevated temperatures (<800°C), the Al2O3 was partially reduced by Ni, and the evidence of Ni-Al intermetallic alloy formation was observed. Further efforts include the construction of a UHV system capable of preparing interfaces suitable for interfacial structure and adhesion studies.