His main research interests are in the areas of networked control and information theory, multi-agent systems, time-delay systems, linear multivariable systems theory, system identification, robust control, and in broad applications of control theory and techniques. He is the author of several books, among which are Control-Oriented System Identification: An H-infinity Approach (with G. Gu, Wiley-Interscience, 2000), Stability of Time-Delay Systems (with K. Gu and V.L. Kharitonov, Birkhauser, 2003), Towards Integrating Control and Information Theories: From Information-Theoretic Measures to Control Performance Limitations (with Song Fang and Hideaki Ishii, Springer, 2016) and Limits of Stability and Stabilization of Time-Delay Systems: A Small-Gain Approach (with Jing Zhu, Tian Qi and Dan Ma, Springer, 2018).