Trevor Fetter, CEO and chairman of the one of the nation’s largest hospital chains, Tenet Healthcare, will be leaving those roles by March 15, 2018.

The company’s announcement doesn’t come with any anointed successor, as it said Russell Reynolds Associates to conduct a search for a new CEO. Tenet’s current independent lead director, Ronald Rittenmeyer, will become executive chairman effective immediately, serving as the senior-most executive in the company.

“The changes announced today will ensure Tenet remains focused on providing high quality care to patients, innovating in ways that meet the demands of today’s healthcare market, and driving operational and financial performance in a manner that maximizes shareholder value,” Rittenmeyer said. “The Board of Directors thanks Trevor for his significant contributions to Tenet and appreciates his commitment to remain with the Company during the transition period. During Trevor’s tenure, Tenet has built a strong enterprise that is aligned with the trends driving healthcare, and which provides multiple channels for growth across the company’s Hospital, Ambulatory and Conifer segments.”

Fetter first came to Tenet in 1995, working his way up to president in 2002, CEO in 2003 and then chairman in 2015. He had previously spent seven years as an executive at film giant Metro-Goldwyn-Mayer Studios, or MGM.

His long tenure as CEO had been rockier recently. Tenet had been seen as underperforming financially, with a potential proxy fight in the making after two representatives of its largest shareholder, Glenview Capital Management, quit the Tenet board earlier this month.

The Dallas-based health system is one of the largest in the U.S., owning or managing 77 hospitals and more than 1,000 medical offices.