Paul Horowitz is Professor of Physics at Harvard University, where he originated the Laboratory Electronics course in 1974 from which emerged The Art of Electronics (1980). He was one of the pioneers of the search of intelligent life beyond the Earth, and one of the leaders behind SETI. Other research interests include observational astrophysics, x-ray and particle microscopy, and optical interferometry. He is the author of some 200 scientific articles and reports, has consulted widely for industry and government, and is the designer of numerous electronic and photographic instruments. Winfield Hill is by inclination an electronics circuit-design guru. He has held positions at numerous organisations, including Harvard University's Electronic Design Center and Sea Data Corporation. Currently he is the Director of Electronics Engineering at the Rowland Institute at Harvard where he has designed some 250 electronic instruments. Recent interests include high-voltage RF (to 15kV) and precision high-current electronics (to 6000A).