American complexity scientist and systems theorist John Casti, Ph.D., is cofounder of The X-Center, a Vienna-based research institute focusing on human-caused extreme events and how to anticipate them. Previously, he was a senior research scholar at the International Institute for Applied Systems Analysis, where he headed an initiative on Extreme Events in Human Society. He worked for many years at the Santa Fe Institute and the RAND Corporation, and has also served on the faculties of Princeton University, the University of Arizona, and New York University. A former editor of the journal Complexity, Casti has published nearly twenty volumes of academic and popular science and received his Ph.D. in mathematics from the University of Southern California. He lives in Vienna, Austria.