Mau Hsiung Chen is a staff physicist in the Theory and Modeling Group of Physics Division. He received his B.S. in Physics from National Taiwan Normal University in 1962 and his Ph.D. in Physics from University of Oregon in 1972. He was a Research Associate afterwards and subsequently a Research Assistant Professor at University of Oregon. During this period, he worked on atomic inner shell processes and physics of highly-charged ions. In particular, he carried out seminal works on relativistic calculations of Auger and fluorescence yields for atoms and few-electron ions. In 1984, he joined T Division at LLNL as a physicist to work on the x-ray laser project. Over the years, he has performed theoretical studies of relativistic electron correlation problems in atomic structure and transition rates, electron- and photon-ion interactions, and various atomic processes in hot plasmas. He has also developed relativistic codes to calculate LTE opacity for plasmas and relativistic atomic physics package for NLTE plasma modeling. Mau is a Fellow of the American Physical Society.