Ireland bid to become the first team to win an unprecedented third successive Six Nations title with second favourites France getting the tournament underway at home to ailing Wales on Friday.
AFP Sport runs the rule over the strengths and weaknesses of the six title contenders (according to last year's finishing order):
Ireland
Strengths: They may have not been at their best in the November tests but they still managed to beat both Argentina and Australia.
Their defence was especially strong which is a testament to Simon Easterby, who gets his chance as head coach for the tournament with Andy Farrell away on British & Irish Lions duty.
A strong pack and outstanding backs, the vast majority of whom have been the backbone of the past two title winning sides augurs well.
Weaknesses: Former Ireland fullback Hugo MacNeill told AFP the Irish will be exposed at the pivotal post of fly-half where they have still failed to fill the hole left by Johnny Sexton.
Jack Crowley, 25, guided the Irish to the Six Nations title but by the end of November it was 21-year-old Sam Prendergast starting, as he will against England on Saturday.
Competition can be a positive but for MacNeill the fact neither has 'stamped his mark' on the position illustrates that they are a "distance away from being Grand Slam winning fly-halves".
France
Strengths: The return to the Six Nations fray of scrum-half and captain Antoine Dupont, after his decision to miss last year's tournament paid off with Olympic sevens gold, will send shivers down the spines of all France's rivals.
The 28-year-old is reunited at test level with his Toulouse halfback partner Romain Ntamack, who missed last year's Six Nations because of injury.
Their natural chemistry and Dupont's individual brilliance could prove the difference this time and secure them a second Grand Slam. Not to mention the metronomic boot of Thomas Ramos who returns to full-back.
Weaknesses: They are missing some key players, Charles Ollivon for the entire tournament and Gael Fickou and Damien Penaud for at least their opener.
There are question marks too as to whether they can deliver. Despite their immense talent they have failed to match that with trophies under Fabien Galthie: just the 2022 Grand Slam so far.
England
Strengths: In Marcus Smith they have a player capable, like Dupont, of changing the outcome of a match.
Their results last year on face value do not look impressive but several were close run things, including the series in New Zealand, and coach Steve Borthwick may feel all they need is a touch of good fortune to turn things round.
Borthwick's call to replace Jamie George with Maro Itoje as captain could prove inspired too.
Weaknesses: Like France England will be missing stalwarts, including George for at least the opener, but while they may return the problems run deeper than absentees.
For England's 2003 World Cup winning coach Clive Woodward, it is a lack of a cutting edge in attack that is their Achilles heel even with Smith in the side.
"England’s attack was poor in the autumn. For England to find their next level, something has to happen and fast," he opined in his Daily Mail column.
Scotland
Strengths: Many see them as dark horses for the title which would be their first ever Six Nations crown.
They have exciting backs in try-scoring machine Duhan van der Merwe, fullback Blair Kinghorn and the magician waving the magic wand in his inimitable, sometimes frustrating, style Finn Russell at fly-half.
If they fire it could result in a Grand Slam decider with France in Paris in the final round of matches in mid-March.
Weaknesses: The absence of captain and centre Sione Tuipulotu for the entirety of the tournament is a huge blow but it is the pack that is a cause for concern.
If they get rolled over it will starve the backs of the possession they can use to carve up opposition defences.
Also there are questions over whether head coach Gregor Townsend is the man to turn them into champions in what is his eighth year in charge.
Italy
Strengths: A vibrant crowd-pleasing backline which shone in the last Six Nations, to the extent that centre Tommaso Menoncello was voted by fans the player of the tournament.
Coach Gonzalo Quesada has not only got them playing with flair but the whole side is brimming with confidence and self-belief.
Treviso's qualifying for the Champions Cup last 16 has given them a timely boost and reflects the progress that has been made.
Weaknesses: A poor set of results in November may have given Quesada a reality check.
Also, like the Scots, there are questions over the scrum. And despite the progress at club and test level, there is for the moment a lack of depth if key players suffer injuries.
Wales
Strengths: On a losing run of 12 matches it is hard to be optimistic but the return of experienced hands Liam Williams and Josh Adams could help the younger players settle, which will be all the more important in the cauldron of the Stade de France on Friday.
They have a talented backrow including captain Jac Morgan and in lock Will Rowlands one of their stars from the 2023 Rugby World Cup.
Weaknesses: Lack of confidence engendered by the losing run and inexperience at fly-half.
Perhaps the main one is the feeling head coach Warren Gatland's time has run its course but Welsh rugby's problems run deeper than the failings of just one man.