“We had seven hundred bad days,” Senator George Mitchell, the US’s special envoy to Northern Ireland said, “and then one good day.”

Next April, the Good Friday Agreement will mark its 25th anniversary, the anniversary of that good day. David Donoghue was one of the chief negotiators for the Irish government at that time and his book One Good Day tells the story of the road to the Good Friday Agreement.

It is a story of great breakthroughs and great sacrifices by men like David Trimble and John Hume but it is also a story of those personalities and how peace was built through relationships, at that stage with Bertie Ahern and Tony Blair creating foundations and later through the unlikely alliances such as Martin McGuinness and Peter Robinson, a dynamic wonderfully described in Tommie Gorman’s book.

David Donoghue at his home in Monkstown. Photo: Bryan Meade

The claustrophobic atmosphere within Castle Buildings in Belfast as they moved towards Good Friday in 1998 is a compelling part of the story. The buildings were like a “prison” with many desperate to escape, Donoghue recalls. Along those corridors there might be involuntary exposure to leaders others weren’t meant to acknowledged but it all helped to move all parties closer to that final agreement.

The Good Friday agreement is 25 years old next April and Donoghue remains optimistic even if he feels it has not achieved its potential, while the creative ambiguity at the heart of the agreement is harder to maintain in a world polarised by the consequences of Brexit.