Bromination and iodination of hydrosilanes and germanes were studied. Treatment of hydrosilanes with an excess of ethyl, propyl, or allyl bromide in the presence of a catalytic amount of PdCl2 or NiCl2 gave bromosilanes in good to high yield by hydrogen–halogen exchange. By using methyl, propyl, or allyl iodide as the iodine source, similar iodination of hydrosilanes was readily performed. Halogenation