Aon names DeBrunner to lead global accounting functions

He will succeed Michael Neller, who has held the role since 2018. 

Aon plc has appointed David DeBrunner as Senior Vice President, Global Controller, and Chief Accounting Officer, effective 15 September. 

He will report directly to Aon CFO Edmund Reese and will be responsible for overseeing the firm’s accounting and financial reporting functions.

DeBrunner brings over 30 years of financial services experience, including leadership roles in accounting, regulatory reporting, and strategic finance. 

Most recently, he served as Vice President, Chief Accounting Officer, and Controller at Ally Financial Inc., where he played a key role in the company’s transition to a bank holding company and its IPO. 

Earlier in his career, DeBrunner held senior roles at Fifth Third Bancorp, where he centralized accounting functions and introduced technology solutions to improve operations.

He will succeed Michael Neller, who has held the role since 2018. 

Neller is transitioning to a new position within Aon as Deputy Global Chief People Officer and head of Total Rewards and Talent Development, as announced in March 2025.