Two decades ago, O'Brien was agitating about price of condoms
TONY O'Brien is an outsider who became an insider.
Two decades ago, when he was agitating about the price of condoms, few would have predicted that he would one day be chosen as the man to lead the health service in troubled times.
He was chief executive of the Irish Family Planning Association (IFPA) during the 1990s when social issues like the wider availability of contraception and abortion counselling provoked regular bouts of public handwringing.
In 2002, he called on the then Taoiseach Bertie Ahern to immediately enact abortion legislation.
However, he changed career course in 2003, spending two years doing a master's in management practice. He left the world of charity groups and protest language behind.
He has since held various posts in the state-funded health service, overseeing the Breastcheck and cervical screening programmes.
He also took over from former cancer tsar Tom Keane to oversee cancer services after the unpopular hard work -- closing units in smaller hospitals -- was already done.
Since last year, he has headed the Department of Health's Special Delivery Unit, which monitors and works with hospitals to cut patient delays. Its biggest test will be this autumn and winter.
He is now a key part of the Health Minister's inner circle and was James Reilly's hand-picked choice as director general of the Health Service Executive.
In the revamped HSE, he will have fewer legal powers than the outgoing chief Cathal Magee, as much of the control will return to the Department of Health. But because of his connections to the minister, he will be less isolated and therefore more dominant.
Although he has held a number of senior positions, they have been largely managerial, keeping services running efficiently and budgets in check.
He was known to get particularly defensive when journalists preferred to quiz him on why a significant number of women were not turning up for free Breastcheck screening rather than concentrating on the self-congratulatory press release figures.
He still speaks with a thick English accent, having spent his formative years in the UK, although his family are from Connemara in Galway.
He is 49 and lives in Co Louth with his wife and two children.