The changes of head coach are the ones that have captured most headlines ahead of the 2020 Six Nations.
In total, there are four new names heading up the sextet of teams.
Andy Farrell has stepped up into Joe Schmidt's shoes for Ireland and ex-Scarlets head coach Wayne Pivac has succeeded Warren Gatland for Wales.
Meanwhile, Fabien Galthie will aim to spark a new era with a young French side, whilst Italy will go into this tournament with Franco Smith before making a more permanent appointment by the summer.
However, some changes in the backroom teams are also intriguing.
Mike Catt
Since Ireland's downturn in form after an outstanding 2018, the focus has been on trying to bolster the variety in attack, with Joe Schmidt's side increasingly seen as one-dimensional in the final stages of his tenure.
While wholesale changes of personnel or style mightn't be visible until the summer according to Donal Lenihan, we may yet see the fingerprints of Farrell's new attack coach over the next couple of months.
Mike Catt, for one, will have a degree of clout when it comes to a shift in Ireland's attacking game, exemplified by the lengthy discussion he undertook at Jonathan Sexton's abode before Christmas about the future plans for his specialist area.
His most recent role was as part of Conor O'Shea's Italy setup. Positive results against tier one opposition largely eluded Italy but they did manage to accumulate double figures for tries in both the 2018 and 2019 championships, while also setting their two highest points for tallies of the decade in Catt's final two years of involvement.
Italy also scored more points than ever at a Rugby World Cup in the 2019 edition, having played a match fewer than previous editions due to Typhoon Hagibis - highlighting greater ruthlessness against weaker opposition as they doubled their 2015 try tally four years on.
Matt Proudfoot
Eddie Jones' side came very close to the pinnacle three months ago.
But just days on from dismantling the All Blacks so impressively, England proceeded to fall flat against a powerful South Africa side on the grandest stage.
One area they lost the arm-wrestle in was the battle of the scrums and packs.
Which makes it all very intriguing to see England hire the forwards coach who helped hone that Springbok strength.
Matt Proudfoot goes from South Africa forwards coach to linking up with England and it's a sign Jones is targeting incremental improvements in areas where they just fell short in an otherwise impressive 2019 Rugby World Cup, with the head coach saying as much when he indicated his hope that Proudfoot "can take the forwards to another level".
Shaun Edwards
Les Bleus go into this Six Nations with an eye very much on the future - to 2023 at least.
France host that year's World Cup and will hope to be out of the doldrums of the last decade by that time, hence why they have named a young squad and 26-year-old captain in the shape of Charles Ollivon.
But one area they are clearly looking to improve on is in defence.
The French have brought former Wales defence coach Shaun Edwards on board in the hope that he can do for them what he did for Warren Gatland.
And from the efforts they have made to get their man, it's clear they see him as a vital cog in the current cycle to 2023.
"France came in and I sensed they really wanted me, so that's why I went," Edwards told The Guardian.
Last time they faced England in the Six Nations - albeit away - they shipped six tries.
Sunday's clash at the Stade de France will give an indication of what improvements the home side have made in Edwards' brief involvement thus far.
Follow Ireland v Scotland (kick-off 4.45pm) on Saturday via our live blog on RTE.ie/Sport and the News Now app or listen live on RTÉ Radio 1's Saturday Sport. Highlights on Against the Head, Monday at 8pm on RTÉ2 and RTÉ Player.
