Three senior executives of Sunoco LP (NYSE: SUN), including the partnership’s president and CEO, will retire at the end of 2017, the company said on June 22.

Robert “Bob” W. Owens, who has led Sunoco since 2012, will step aside from his position as president immediately and as CEO on Dec. 31. Joe Kim, executive vice president and chief development officer for Sunoco since 2015, has taken over as president and COO.

Following his retirement, Owens will serve as a consultant to Sunoco through 2019.

Sunoco executives Cynthia Archer, executive vice president and chief marketing officer; and Boyd Foster, executive vice president, manufacturing and distribution, will also retire on Dec. 31.

“We thank Bob for his many years of strategic leadership, which has resulted in an impressive list of accomplishments for both the employees and the unit holders of Sunoco and wish him and his family the best,” said Kelcy Warren, Chairman of Energy Transfer Equity, the entity that owns the general partner of Sunoco, in a statement. “While we are sad to see Bob go, we are excited for the next generation of leadership at Sunoco to take on larger roles. Joe is an exceptionally talented leader and he has played a significant role in the planned transformation of the partnership from a retail-based business into a premier nationwide fuel supplier.

“Additionally, the appointment of Joe as president and COO and Bob continuing as CEO through year-end will ensure an orderly transition as we move through the divestment of our retail operations during the coming months,” Warren said.

Owens joined Sunoco as senior vice president of marketing where he was responsible for Sunoco’s retail network, wholesale marketing and transportation operations, and commercial supply and trading activities for crude oil, refined products, and petrochemicals. Prior to joining Sunoco, he held executive positions with Ultramar Diamond Shamrock Corp., Amerada Hess Corp. and Mobil Oil Corp. Owens is a graduate of California Polytechnic State University with a bachelor’s degree in business administration and an MBA from the Kellogg Graduate School of Management at Northwestern University.

Kim has been responsible for the Partnership’s strategic development and planning overseeing both business development and Sunoco’s real estate portfolio. Prior to joining Sunoco, he held various executive positions, including COO for Pizza Hut and senior vice president, retail strategy and growth, for Valero Energy. Kim began his career with Arthur Andersen. He is a graduate of Trinity University with a bachelor’s degree in business administration.