The preparation and characterization of supported bimetallic clusters has been an active area of research following the initial pioneering efforts of Sinfelt in the late 1960s and early 1970s [1–3]. Because of the importance of supported bimetallic and multimetallic catalysts in industrial applications such as petroleum reforming and the control of automotive exhaust emissions, research on better ways of synthesizing and characterizing these catalytic materials is continuing to advance, as evidenced by the very large number of research papers which have recently appeared in the literature. Of particular interest are the preparative variables which control the formation of bimetallic particles.