Bacillus plays a vital role in microbiology research. This widespread and diverse group of bacteria synthesizes a large array of antibiotics, fine chemicals, vitamins, and industrial enzymes. Bacillus bacteria serve as production platforms for biofuels and ecofriendly pesticides. Some species are useful as probiotics or in vaccine production; others play important roles in health care, food safety, and bioterrorism prevention. Bacillus research provides deep insights into the physiology, development, and behavior of bacterial cells. The Bacillus Genetic Stock Center (BGSC) maintains a centralized collection for useful Bacillus strains. Each year, BGSC strains are used for hundreds of innovative projects nationwide, resulting in peer-reviewed publications and US patents, undergraduate teaching lab experiences, and high school science fair projects. NSF support will strengthen the nation's scientific infrastructure by ensuring that this resource remains available to America's scientific research and education communities.<br/><br/>The BGSC will collect, maintain, document, and distribute Gram-positive, endospore-forming bacteria, not only from Bacillus but from many closely related genera. The backbone of the collection is devoted to B. subtilis, a model organism and biotechnology workhorse. Included are two complete knockout libraries covering every non-essential gene in the organism and a third "knock-down" library covering the essential genes. A wide variety of genetic tools for modulating gene expression and for constructing new strains are also stocked. The collection is rounded out with sizable holdings of the biopesticides B. thuringiensis and Lysinibacillus sphaericus, the thermophile Geobacillus, the food spoilage organism B. cereus, the plant growth-promoting Paenibacillus, and other important species. Cultures will be collected and stored cryogenically at a secure site at the Ohio State University and made available to qualified scientists and educators. Strain data will be made publicly available on the BGSC website (http://bgsc.org) and integrated into Bacillus gene and genome databases in the USA and Europe.