Awarded the CBE for services to the region’s economy in 2001, the Belfast man’s reach has extended into the public and private sectors and also to the top of government.
Despite his experience and connections, the independent financial-and-management consultant had a low public profile until this month.
That changed when the Nama controversy flared up. His role as an adviser to the Dublin government’s bad bank, and his association with a potential US buyer of Nama’s Northern portfolio, became the focus of parliamentary scrutiny.
Tughans, the Belfast legal firm whose role in the Nama sale is also being examined, has said Mr Cushnahan occupied a “self-contained” office in its city centre building.
Mr Cushnahan was appointed as an external member of Nama’s NI committee in 2010, on the recommendation of former Stormont finance minister, Sammy Wilson, and resigned three years later, citing his age and family.
While not a household name for the majority of his career, he is known in boardrooms across Northern Ireland.
Before retiring from banking, the past pupil of St Malachy’s College, Belfast, held management-director positions in two leading financial institutions.
He was not short of work in his consultancy career and held numerous executive and non-executive board positions within the public and private sectors.
In the political sphere, he is former director of the Office of the First Minister and Deputy First Minister. He has also been chair of OFMDFM’s audit and corporate governance committee; chair of the ministerial advisory panel to Stormont’s performance and efficiency delivery unit; and a panel member of its capital realisation taskforce.
He is a past chairman of Belfast Harbour Commissioners, WineFlair (NI) Ltd, and an ex-director of the Northern Ireland Science Park Trust Foundation.
The corporate business expert was a non-executive member of the Northern Ireland Housing Executive’s audit committee, but resigned to become chairman of the now-defunct housing maintenance company, Red Sky.
Belfast-based Red Sky went bust in 2011, after finding itself at the centre of a Stormont controversy — auditors expressed concern about potential over-charging for work carried out for the Housing Executive.
In an official report in 2012, the Northern Ireland Assembly’s Public Accounts Committee criticised Mr Cushnahan for involving himself in negotiations between Red Sky and the NIHE over the maintenance contracts dispute.