A personal view of molecular technology and how it has changed biology

I have had the pleasure of practicing biology and technology development for the past 35 yearssfirst at the National Institutes of Health (NIH) for 3 years, then at the California Institute of Technology (Caltech) for 22 years, subsequently at the University of Washington (UW) for 8 years, and finally at the Institute for Systems Biology (ISB) for the past 2 years. In each case, my geographical transitions were prompted by exciting new opportunities and evolving visions of how biology should be practiced. The technology developments I have been associated with over this period helped to catalyze two emerg-ing paradigm changes in biology: systems biology and predic-tive/preventive medicine. My career has been driven by two imperatives from my Ph.D. advisor, Bill Dreyer (Caltech). First, ªAlways practice biology at the leading edge.º For much of my career, this leading edg