For one of Ireland's most famous and influential public figures, Bono has managed to maintain a remarkable degree of privacy about his personal life. That is no accident. Protective of his family and those nearest to him, he also knows that the moment he articulates his personal beliefs and values, there are those who will try to pigeonhole him, to put him in a neat box. He has spent his career trying to break out of - and think outside of - that kind of box.
So, why agree to an interview now, with no pre-conditions and no promotional value?
The clue is in the series title: The Meaning of Life, with Gay Byrne. Bono's musical career, his activism and his personal life are all about leading a meaningful life and Gay Byrne is one of the very few broadcasters or journalists in the world whom he respects and trusts enough to do an interview of this nature.
Two days before his 53rd birthday, Bono took time out of the studio, where U2 are recording their latest album. He wanted a clear space between this conversation and all the promotional interviews that will surround that album's release in the autumn, because, having watched previous episodes, he understood that this was not an interview about the album or the band. It was much more personal than that.
What emerged was a remarkably candid, thoughtful, funny and revealing conversation about the things, the beliefs, the people and the God that give Bono's life meaning.
Speaking about the interview Gay said:
"Bono is one of the people who I have always wanted to feature on the Meaning Of Life. For one of Ireland's most influential figures he has managed to maintain a remarkable degree of privacy. We had spoken many times about doing the interview as I knew this would be very different to any we had done in the past.
Many people will be surprised that Bono has a deeply rooted belief which permeates his everyday life and motivates all his campaigning work. Nothing was off limits and he opened up about his innermost beliefs, his religion, his family and of course the influence of his beliefs on U2."
Watch The Meaning of Life with Gay Byrne, Sunday 3 February 2013 at 10.35pm on RTÉ One