Effective July 1, 2009, Professor Sorin Popa assumes the position of chair of the UCLA Department of Mathematics. A professor at UCLA since 1987, Popa is a world-leading researcher in the areas of functional analysis, operator algebras, subfactor theory, and ergodic theory. His honors include a Guggenheim fellowship in 1995 and two invited addresses at the International Congress of Mathematicians, most recently in 2006 as plenary speaker. He has frequently held visiting positions in France, and from 1996 - 1998 was professor at the University of Geneva. Acting Dean Joseph Rudnick of the Division of Physical Sciences is enthusiastic about Popa's appointment and praises outgoing chair Professor Christoph Thiele for the impressive strides the department has made during his three year tenure, expressing his belief that Thiele will be “remembered as one of the great chairs of your department, indeed the campus.” Congratulations to Professor Thiele for his extraordinary service and best of luck to Professor Popa in his new role.