Werner Enterprises has promoted Derek J. Leathers chief executive officer as part of a series of planned transitions in executive management.

Leathers was previously the company’s president and chief operating officer and has been with Werner for more than 17 years. He replaces Clarence L. Werner, the company’s founder and first driver, who will remain the executive chairman of the company.

In his Werner career, Leathers has held executive management roles leading several organizational service offerings including Werner’s Mexico cross-border operations when he joined the company in 1999. He also oversaw the asset-based trucking businesses and development of Werner’s brokerage, freight management, intermodal and global logistics business units.

Leathers became Werner’s president in 2011 and he holds an economics degree from Princeton University.

Other planned transitions include H. Marty Nordlund who was promoted senior executive vice president and chief operating officer. Nordlund was previously senior executive vice president of specialized services. In his new role, Nordlund will have executive operating responsibility for the company’s trucking and logistics business units.

Jim S. Schelble was promoted to executive vice president and chief administrative officer. Schelble was previously executive vice president of marketing and driver resources. In his new role, Schelble will lead driver recruiting, Werner’s driver school network, safety, human resources, pricing and corporate communications.

Gerald H. Timmerman was elected as a company director to fill an open position. Timmerman was previously a director of the company from 1988 to 2011. Since 1969, Timmerman has been and currently serves as president of Timmerman & Sons Feeding Co. He has also served as the president of Timmerman Feeding Corporation.

Werner Enterprises is an Omaha, Neb.-based transportation and logistics company with coverage in North America, Asia, Europe, South America, Africa and Australia.