2001-06, Dean of Physical Science, University of California, Los Angeles. 2006-09, Assistant Director, Mathematical and Physical Sciences Directorate, US National Science Foundation (NSF). Since 2009, President, Hong Kong University of Science and Technology. Member, American Mathematical Society. Elected Member, US National Academy of Engineering (NAE). Elected Fellow: Institute of Electrical and Electronic Engineers (IEEE); Society of Industrial and Applied Mathematics (SIAM); American Association for the Advancement of Science (AAAS).