Petar V. Kokotovic, native of Belgrade, Yugoslavia, was invited to the United States in 1965 to present a series of seminars on control system design. Soon after he joined the University of Illinois, where he remained for 25 years and held the endowed Grainger Chair. In 1991 he joined the University of California, Santa Barbara, where he directed the Center for Control Engineering and Computation until 2003. In the 1960's, Kokotovic developed the sensitivity points method, a precursor to adaptive control, still in use for automatic tuning of industrial controllers. In the 1970's, he pioneered singular perturbation techniques for multi-time-scale design of control systems and flight trajectories, which found widespread applications. One of them led to the discovery of a fundamental relationship between the slow and fast phenomena and strong and weak connections in dynamic networks. In the 1980's, Kokotovic and coworkers identified the main forms of adaptive systems instability and introduced redesigns, which made adaptive controllers more robust. As a long-term industrial consultant, Kokotovic contributed to the design of the first computer controls for car engines at Ford, and to power system stability analysis at General Electric. Kokotovic's current research is in nonlinear control, both robust and adaptive. He initiated the development of a popular nonlinear recursive design back-stepping, and its use for robust nonlinear control of axial compressors for jet engines, as a part of a multi-university program in collaboration with United Technologies Research Center. Kokotovic is one of the highly cited authors in his field and in all of engineering. He has supervised 35 Ph.D. students and 20 postdoctoral researchers. With them he co-authored numerous papers and ten books.