Although considerable attention has been paid to the use of microbial genomics in medicine, genomic information also promises to make an important contribution to a diverse range of other environmental, food, and industrial applications of biotechnology. As gene sequencing technology becomes more routine, researchers are determining the sequences of more obscure microorganisms and delving into the diversity of the microbial world with the aim of discovering new products. It is hoped that genome data on nonpathogenic bacteria will lead to the discovery of biocatalysts resistant to extremes of pH, temperature, or solvents; nutritionally beneficial bacteria for probiotics; new types of streptomycete antibiotics; and microorganisms with enhanced capabilities to degrade xenobiotic compounds at contaminated sites or leach minerals in biomining. In this issue, Nelson et al. (see p. 1049) summarize recent progress in microbial genome projects, describe the challenges in sequencing a nonpathogenic microorganism, and briefly discuss the potential of complete genome sequence information for providing insights into ways of engineering new and improved activities.