U.S. Army Gen. David Petraeus, a Princeton alumnus and commander of the U.S. Central Command, urged members of the class of 2009 to pursue public service -- stressing that the best and brightest are needed to tackle local, national and international challenges.

Julie E. Cohen, Professor of Law, Georgetown University Law Center

Keynote speaker: David Plouffe, chief campaign manager for Barack Obama 

Michael Cohen, Director of Special Projects, Avara Institute for Environmental Studies.

Arthur (Tim) Garson Jr., executive vice president and provost of the University of Virginia and author of  `Health Care Half Truths: Too Many Myths, Not Enough Reality`