The HGP is being conducted as a collaboration between large-scale sequencing centers coordinated by the National Institute for Human Genome Research and the Department of Energy. Following the developmental phase resulting in genetic and physical maps and technology for high throughput sequencing, the US project was organized into 9 large-scale genomic sequencing centers distributed among universities and research institutes. Each center has focused on a specific portion of the human genome, determined by scientific interest, and each center is applying a slightly different organization and technical approach to developing pilot scale sequencing efforts with capabilities of between 2 and 10 million bp. In addition, at least 5 international centers are similarly developing sequencing capacity sufficient to complete a substantial portion of the human genome sequence. The US centers are presently located at Baylor College of Medicine, Houston, Tex; University of Oklahoma, Norman; University of Texas Southwestern Medical Center, Dallas; Stanford University, Stanford, Calif; the Whitehead Institute/Massachusetts Institute of Technology, Boston; University of Washington, Seattle; Washington University, St Louis, Mo; the Institute for Genome Research, Baltimore, Md; and the Joint Genome Institute of the Department of Energy, Walnut Creek, Calif. The efforts remain highly interactive and collaborative while competing for scale-up funds through a National Institutes of Health grant mechanism.