The present invention includes bivalent or multivalent nucleic acid molecules or complexes of nucleic acid molecules having two or more target-specific regions, in which the target-specific regions are complementary to a single target gene at more than one distinct nucleotide site, and/or in which the target regions are complementary to more than one target gene or target sequence. Also included are compositions comprising such nucleic acid molecules and methods of using the same for multivalent RNA interference and the treatment of a variety of diseases and infections.