The U.S. Army Corps of Engineers has released updated guidelines on the use of single-step design-build. In response to outcry from the design community, the guidelines emphasize that the two-phase selection procedure is the only design-build contracting method authorized for civil works and for work the Corps performs for other agencies. The guidelines also stress that two-step design-build remains the preferred method for military construction, although single-step design-build may be used for some military construction projects under certain conditions. Unlike two-phase design-build, single-step design-build does not involve short-listing, so firms invest significant time and resources pursuing contracts but have a much smaller chance of winning the work. The expense of single-step competitions prevents many contractors and designers from competing.