Pederson's development of Spice (Simulation Program with Integrated Circuits Emphasis) was the crowning point of an illustrious career that covered a half-century in teaching and research—with over half of it at the University of California at Berkeley. Beginning in the vacuum-tube era, Pederson devoted his efforts to the design and performance of electronic circuits that eventually evolved into transistors and, ultimately, into large-scale ICs. Spice was a landmark combination of software engineering, numerical analysis, and modeling of transistors for use in ICs. For more than 25 years, Spice has been the standard means of simulating circuits at the transistor level. At U.C. Berkeley, he became the inaugural E.L. and H.H. Buttner Professor of Electrical Engineering. Before his retirement in 1991, his research was reported in more than 100 technical publications.