In situ X-ray absorption spectroscopy (XAS) has been used to elucidate the structure of binary Cu-Zn and ternary Cu-Zn-Al methanol catalysts in the reduced state. The XAS results of the binary catalysts show the features of a metallic Cu phase after reduction at 220°C. The structure of the reduced ternary catalysts is found to depend critically on both the copper concentration and the reduction temperature. In contrast to the binary catalysts, reduction at 220°C does not result in any significant change as compared with the calcined state. At 260°C, reduction of the copper phase to the metallic state is accomplished, and the crystallite size or degree of order of the metallic Cu is found to increase with the copper content