The present invention provides oligomeric compounds having sufficient complementarity to hybridize to a nucleic acid target and methods for their use in modulating gene expression. In one embodiment the oligomeric compounds comprise double stranded constructs wherein one of the strands capable of hybridizing to a nucleic acid target, and has a plurality of modified ribofuranosyl nucleosides at defined locations. The presence of modifications at such defined positions greatly enhances the properties of the corresponding compositions.