Iogen Corporation has been operating a demonstration plant for the conversion of wheat straw to ethanol since 2004. The process includes a pretreatment with steam and dilute sulfuric acid, followed by enzymatic hydrolysis of the cellulose, and then fermentation of the glucose and xylose to ethanol by using recombinant Saccharomyces. The ethanol is finished as E85 fuel for commercial and fleet use. The demonstration plant is the final step in scale-up of the process prior to commercial operation. This presentation describes the operation of the demonstration plant to date and Iogen's plans for deploying commercial plants that produce ethanol from cellulose.