The XPS spectra of gamma-alumina were collected with a VSW HA150 using monochromatic AlKαx-radiation. Monochromatic radiation provides a distinct clarity to the peak structure in the valence band of gamma-alumina due to the absence of interfering x-ray satellites from the intense O2sregion. Variations in the intensities and peak separation of the two-peak structure in the valence bands of the oxides, hydroxides, and oxyhydroxides of aluminum allow one to distinguish between these compounds. The valence band, survey, and the Al2s, Al2p, O1s, and C1score levels are reported.