One of the pioneers of complexity science and systems theory, John L. Casti, Ph.D., is Senior Research Scholar at the International Institute for Applied Systems Analysis, where he heads an initiative on Extreme Events in Human Society. He worked for many years at the Sante Fe Institute and The RAND Corporation, as well as serving on the faculties of Princeton, the University of Arizona, and New York University. A former editor of the journal Complexity, Casti has published nearly 20 volumes of academic and popular science and received his Ph.D. in mathematics from the University of Southern California. He lives in Vienna, Austria.