Tom Klein will step down by year end from his role as CEO and president of Sabre as well as leave its board.
He will continue to serve as CEO of the travel technology giant while the board hunts for his successor.
In a statement, Klein said:
"We have transformed Sabre into a dynamic software company and the business is positioned for continued consistent growth, so my successor will have a strong hand to play."
No explanation for the decision was provided. Klein has been CEO since 2013.
He still has six months of tenure to go. But when the history books are written, Klein's hallmark accomplishment may well turn out to be having successfully piloted his company to its debut on the public markets in April 2014.
He also helmed the company as its stock price rose from $16 at its IPO to a close today at $27.
He delivered the earnings growth and revenue growth the company's private backers needed to exit their investment, while shedding debt and making acquisitions, such as a $411 million consolidation of its Asian Pacific travel network business.
He oversaw a revving up of the company's product development metabolism. Sabre has rolled out about two dozen products since its IPO.
He has also championed a sales-and-implementation pipeline that promises steady business growth, according to its forecasts and guidance for the markets.
Another pivotal moment came in 2014, when Sabre changed its tune over IATA's New Distribution Capability. After initial hesitation, the company agreed to cooperate with the airline group's effort to push new technology standards for distribution.
Klein has worked at Sabre for more than two decades. He became president in 2010, having previously been executive vice president of Sabre Holdings, responsible for Sabre Travel Network and Sabre Airlines Solutions.
Having started with Sabre when it was still considered a stodgy global distribution system, Klein was integral to the executive leadership that re-positioned the company as a software-as-a-service leader. He guided its diversification into new business lines and income streams.
In public comments, Klein has seemed especially proud of an on-time transitioning of American Airlines' and US Airways' reservations systems onto a combined, unified reservation system.
The smoothness of the switchover was an industry rarity, and also perhaps a grace note for Klein personally, as he began his time at Sabre when it was still a unit of AMR and he once held sales and marketing roles with American.
In a statement, Larry Kellner, chairman of the company's board of directors, said:
"Under his leadership and vision, Sabre is clearly positioned as an innovative technology company and our business has been reinvented to ensure our solutions meet the changing needs of the very dynamic travel industry."
Sabre reaffirmed its full-year guidance and medium-term goals. (See: "Sabre reports continued steady growth, bold forecasts.")
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