Grenell held his U.N. spokesman position from 2001 to 2008, serving under four U.S. ambassadors during former President George W. Bush's administration.
Grenell founded the international consulting firm Capitol Media Partners in 2010, and he has served as "the primary communications adviser for public officials at the local, state, Federal, and international levels, as well as for a Fortune 200 ranked company," according to a White House statement. He also regularly appears on Fox News Channel as a foreign affairs commentator.
In June 2013, Grenell revealed that he had been diagnosed with non-Hodgkins lymphoma and had started chemotherapy. A few months later he announced that he was in remission.
Grenell earned a Bachelor of Arts from Evangel University in Springfield, Missouri, and a Master of Public Administration from Harvard University's John F. Kennedy School of Government.