With the recent commissioning of the National Renewable Energy Laboratory’s (NREL) process development unit, through the support of the US Department of Energy (DOE) Biofuels Program, the technology to convert lignocellulosic biomass to fuel ethanol enzymatically has reached the pilot scale. The next step will be to construct precommercial-scale engineering demonstration units, which will probably be built at or near proposed commercial plant sites, to demonstrate this technology at selected biomass-rich locations in the US. Proper site selection can be critical to these units’ long-term profitability, so DOE and NREL have begun a program to help industrial partners build sound business plans that include detailed siting studies. These studies examine biomass availability and cost projections, delineate site requirements, identify qualifying sites, examine environmental and community impacts, and provide detailed pro forma financial evaluations and projections. The DOE/NREL ethanol project currently supports several plans that help industry identify economically viable commercial opportunities for biomass ethanol.