Byrne's Davy move is a big change of direction
At Davy, Bernard Byrne will replace Kyran McLaughlin, long one of the most powerful financiers in the country, with a personal stake in the firm worth over €50m.
Davy's capital markets bankers manage share and bond deals for large clients.
Joining Davy isn't Mr Byrne's first foray into stockbroking. He led an abortive AIB bid to buy specialist bank Investec earlier this year.
The bid failed but gave him a crash course in the sector. He also oversaw AIB's own €3.4bn flotation. Still, the move to Davy, Investec's bigger rival, is a big departure.
Trained as an accountant, Mr Byrne joined AIB from the ESB in 2010. He was head of retail and business banking before becoming CEO. He'd previously worked in the private sector.