Ligand-stabilized bimetallic Au/Pd colloids may be prepared from 180–200Å Au colloids which can be covered by Pd shells of varying thickness. They can be isolated as solid materials without agglomeration. HREM observations indicate a narrow particle size distribution and reveal a well-defined Au(core)/Pd(shell) structure. This is convincingly confirmed by EXAFS data. Thermal treatment leads to Au/Pd alloy formation at ≥ 500 K, as evidenced by the appearance of characteristic Au-Pd distances in the EXAFS.