Marc Grandisson is the new CEO of Arch Capital Group. Ltd., following the previously announced retirement of longtime leader Constantine “Dinos” Iordanou.

Arch disclosed in a regulatory filing that Grandisson, 50, most recently president and chief operating officer, has been promoted to the CEO slot as well. Iordanou will remain a senior adviser to the management team, however, and also continue as chairman, he said during a Carrier Management interview in August 2017.

“I’ll be 68 years old when I retire in March,” Iordanou told Carrier Management, “but I’m a young 68 and my brain still works well, so why park it and waste it?”

Grandisson has been with Arch since 2001 and worked up the ranks in a variety of executive positions. Before becoming president and chief operating officer, he was chairman and CEO of the Arch Worldwide Reinsurance and Mortgage Groups, and had been promoted to both roles in November 2015.

His latest promotion took place on March 3, according to Arch’s succession plan, the company’s regulatory filing stated.

Iordanou began his insurance career more than 41 years ago. A trained aerospace engineer, he was drawn into the insurance business at age 26 in 1976, thanks to a recruiting initiative from American International Group focused on engineers who could help with satellite launch insurance, a relatively new coverage at the time.

At Arch, Iordanou had been running the Bermuda-based insurer and reinsurer for 16 years. He explained during the Carrier Management interview in August that he was retiring as CEO to spend more time with his grandchildren, pursue charitable work, play golf and travel the world, among other activities.