Kellner joined Sabre as non-executive chairman of the board of directors in August 2013, and brings a strong background in the travel sector in which Sabre operates as a technology provider to leading airlines, hotels, travel agencies and travel management organizations. He has served as president of Emerald Creek Group since 2010. He previously was with Continental Airlines, Inc. from 1995 to 2009 where he served as president and chief operating officer from 2003 to 2004, and chairman and CEO from 2004 through 2009. He was also a member of the Continental Airlines, Inc. board of directors from 2001 to 2009. In addition to Sabre, Kellner also currently serves on other boards of directors, including The Boeing Company and Marriott International, Inc. He holds a bachelor of science in business administration from the University of South Carolina.