Dr Len O'Hagan CBE has been appointed to chair the board of Northern Ireland Water (NIW) for a second term.
The appointment of Dr O'Hagan was announced by Infrastructure Minister Nichola Mallon.
Mrs Mallon welcomed the appointment.
She said: "I'm pleased to announce the appointment of Len O'Hagan to this important post.
"I am confident that with Len's knowledge of the issues facing NI Water, he will continue to make a valuable contribution to the work of the board in his role of chair."
NI Water is responsible for the delivery of water and sewerage services across Northern Ireland. Its board provides independent judgment on a wide range of issues, including strategy, performance, governance and executive appointments.
The appointment is effective from April 1 for a period of up to four years.
Dr O'Hagan is also a director of Belfast Telegraph publisher INM.
He was recently appointed Pro-Chancellor and member of senate for Queen's University Belfast, having previously studied economics at Queen's.
Dr O'Hagan is chair of the All-Island Congenital Heart Disease Network, a director of the College of Anaesthesiologists and a fellow of the Institute of Directors.
His former appointments include chair of Belfast Harbour Commissioners, chair of the Metropolitan Arts Centre, chief executive of the Royal College of Physicians and a director of the Ireland-US Council.
Dr O'Hagan has also held senior roles in international companies such as Smurfit, Fitzwilton and Reed International and holds directorships in a number of private companies.
In 2013, Dr O'Hagan was awarded an honorary doctorate by Queen's for exceptional services to business and commerce.
The NI Water board currently comprises the chair, five non-executive members and four executive members.