The generation of transgenic plants can be a lengthy and difficult process. Transient expression assays have been developed as faster and more convenient alternatives for investigating gene function. These assays often take advantage of the ability of Agrobacterium to transfer foreign DNA into plant cells with intact cell walls. Agrobacterium-mediated transformation is, however, inefficient and shows great variability. In the May issue of Cold Spring Harbor Protocols, Andreas Nebenführ and colleagues from the University of Tennessee present FAST Technique for Agrobacterium-Mediated Transient Gene Expression in Seedlings of Arabidopsis and Other Plant Species, a quick, efficient and economical assay for gene function in intact plants. The technique involves cocultivation of young plant seedlings and Agrobacterium in the presence of Silwet-77. The Silwet-77 facilitates transformation, thus replacing a wounding or device-dependent vacuum step. As one of May’s featured articles, it is freely available to subscribers and non-subscribers alike.