Virus-induced gene silencing (VIGS) is a useful functional genomics tool for rapidly creating plant gene knockout phenotypes that can be used to infer gene function. Until recently, VIGS has only been possible in dicotyledonous plants. However, the development of cloning vectors based on Barley stripe mosaic virus (BSMV) has now made VIGS possible in barley and wheat. VIGS has particular advantages for functional genomics in wheat, where the organism's hexaploidy and recalcitrance to transformation have greatly hindered strategies for the functional identification of genes. In this chapter, methods are presented for using the Barley stripe mosaic virus VIGS system (BSMV-VIGS) to silence genes in hexaploid wheat.