Bus Éireann has announced that chief executive Martin Nolan is stepping down from his position after six years in charge of the state owned bus company.
His role will be assumed in an acting capacity by current Chief Financial Officer Ray Hernan.
Mr Hernan was a former director of finance at Ryanair, while he also previously held senior financial roles with Brown Thomas and Arnotts.
The company is currently preparing a restructuring strategy to address its losses of €5.6m in 2015 and an estimated €6m in 2016.
It is considering removing the Expressway service into a separate subsidiary, which could result in redundancies and inferior pay and conditions for remaining staff.
The strategy is due to be revealed by the end of this month.
Mr Nolan had joined the company in 1997 and held previous roles as Chief Operating Officer and Chief Financial Officer.
In a statement, he noted that his term of office - which had been extended - was due to expire, and that he was especially mindful of the change management process which had been initiated.
He said that in light of those factors, it was the right time to ensure that a new team is put in place to manage the next phase of change and development at Bus Eireann.
He said it had been a great honour to work with the men and women of Bus Eireann and to have been centrally involved in the provision of significant national transport services on behalf of communities across Ireland.
The Chairman of Bus Éireann, Aidan Murphy, thanked Mr Nolan for all that he had achieved, in particular for his leadership of the business through what he called the exceptional challenges of the recession.
He said that critically, plans are being finalised to address the serious financial issues and the company is ready to implement as a matter urgency the structural changes and efficiency initiative required to position the business for future growth and viability.
Incoming acting CEO, Mr Hernan said he was delighted to assume his new role as the company prepares to implement a strategy focused on addressing the financial challenges and efficiency needs of the business.
He said the strategy is urgently required in a much more competitive marketplace.
Shortly before Christmas the longstanding Director of Human Resources at the company Joe Kenny also departed.