Various embodiments of the present invention are directed to methods of forming single-crystal metal-silicide nanowires and resulting nanowire structures. In one embodiment of the present invention, a method of fabricating nanowires is disclosed. In the method, a number of nanowire-precursor members are formed. Each of the nanowire-precursor members includes a substantially single-crystal silicon region and a polycrystalline- metallic region. The substantially single-crystal silicon region and the polycrystalline-metallic region of each of the nanowire-precursor members is reacted to form corresponding substantially single-crystal metal-silicide nanowires. In another embodiment of the present invention, a nanowire structure is disclosed. The nanowire structure includes a substrate having an electrically insulating layer. A number of substantially single-crystal metal-silicide nanowires are positioned on the electrically insulating layer.