David R. Walt is the Robinson Professor of Chemistry at Tufts University and a Howard Hughes Medical Institute Professor. He is also the founding scientist, director, and chairman of the Scientific Advisory Board of Illumina, Inc. He received his B.S. in chemistry from the University of Michigan and Ph.D. in chemical biology from the State University of New York, Stony Brook. His laboratory is world renowned for its pioneering work that applies micro- and nanotechnology to urgent biological problems, such as the analysis of genetic variation and the behavior of single cells, as well as the practical application of arrays to the detection of explosives, chemical warfare agents, air contaminants, and food and waterborne pathogens. Dr. Walt received the National Science Foundation Special Creativity Award in 1995 and the 3M Research Creativity Award in 1989. He has served on a number of NRC committees, including the Committee on Review of Testing and Evaluation Methodology for Biological Point Detectors.