He will report to Nick Studer, chief executive of Marsh Risk, and succeeds John Donnelly, president of global placement, who is set to retire from the business next year.
In the role, Adamantiadis will lead Marsh Risk's global placement and market solutions strategy, working with regional leaders and insurers worldwide to accelerate product innovation and ensure the broker continues to design, structure and place insurance programmes across markets, industries and client segments.
Adamantiadis moves into the global role from his position as chief executive of Marsh Europe, a role he has held since March 2023 after being promoted from CEO of Marsh's Continental Europe division, which he took on in January 2023 following seven years leading the firm's Middle East and Africa region. He joined Marsh in 2018 from Oman Insurance Company, where he served as chief executive for three years, having previously spent 20 years at AIG in various regional management roles spanning Central and Eastern Europe, Russia, Turkey, the Middle East and North Africa.
Tom Geraghty (pictured, right) succeeds Adamantiadis as chief executive of Marsh Europe, effective the same date. Geraghty will be based in Dublin and report to Flavio Piccolomini, chief executive of Marsh International. In the role, he will be responsible for setting the strategic direction of Marsh's Europe region and strengthening collaboration across its businesses to deliver integrated solutions for clients. Geraghty previously served as president of Mercer for Europe, a sister business within Marsh McLennan, giving him prior experience operating within the same regional leadership structure he now leads on the broking side.
The pattern of moves is consistent with how Marsh has handled its European leadership changes in recent years, having previously promoted Adamantiadis himself from a regional role rather than hiring externally when Continental Europe's CEO position became vacant in 2023.
For clients and brokers working with Marsh's European operations, the practical continuity is that both new leaders already have direct, multi-year familiarity with the business and markets they are now taking charge of, rather than needing to build that understanding from scratch.
