Seeing the International Sequencing Consortium's draft of the human genome is highly satisfying. The way in which its 3 billion bases have been determined closely followed the course outlined more than a decade ago by the National Academy of Sciences (NAS) Committee on “Mapping and Sequencing the Human Genome.” Bruce Alberts, now the President of the NAS, was its chairman and I one of its 14 other members. The predictions in our 1988 report, that the human genome could be sequenced over a 15-year period for a cost of three billion dollars, were more accurate than we dared guess. Two more years of work, to fill in gaps and correct mistakes, will result in an almost errorless genetic script for human existence.