Plant viruses cause severe damage and significant economic losses to agriculture. Control of virus usually consist of<br />the elimination of virus vectors (insects, nematodes, fungi, etc), improvement of the sanitary status of the propagation<br />material, the use of resistance sources in breeding programs. The application of the pathogen-derived resistance strategy<br />has opened new avenues to protect plants against viruses. Two molecular mechanisms seem to underlie the engineered<br />protection, the virus transgene-derived protein and the transgene-RNA interference. A few examples that support the<br />efficiencies of these two molecular mechanisms are reviewed here and discussed in light of the potential use of virusresistant<br />transgenic plants in agriculture.