How they match up compiled by Gerry Thornley.
IRELAND
Coach: Eddie O'Sullivan
Capt: Brian O'Driscoll
Grand Slams: One
Championships: 10
Triple Crowns: Six.
Affiliated clubs: 135
Total players: 56,500
Senior male players: 11,500
Forecast: Third
Not that Ireland's more concentrated provincial structures are necessarily translated to the test arena, where the more disparate talents of England, France and even Scotland are harnessed. There is also a nagging suspicion that the aqua-rugby of last November isn't as relevant as it should have been.
Dependant on Brian O'Driscoll yes, but this team (established in virtually every position) has made a quantum psychological leap without Keith Wood. Deep down, if the defence and set-pieces even strengthen a tad more and the match-winners out wide are given space, they are entitled to believe they can beat anybody. At Lansdowne Road - where Ireland has won seven in a row and 10 of its last 11 games - that even goes for France or England.
Player to watch:Geordan Murphy
Deemed a full back by O'Sullivan, Murphy has enjoyed his longest and most prodigious spell in that position for Leicester, and Girvan Dempsey is struggling with groin problems. Whatever the position, the thought of Murphy making a real breakthrough and working with O'Driscoll and Hickie can only enhance Ireland's World Cup prospects.
FRANCE
Coach: Bernard Laporte
Capt: Fabien Galthie
Grand Slams: Seven
Championships: 13
Affiliated clubs: 1,710
Total players: 252,638
Senior male players: 93,470
Forecast: Second
'Les Bleus' campaign hinges on the opener in Twickenham. Lose that and Bernard Laporte will have a freer hand to pursue his intended policy of experimenting during the championship (such as blooding Dimitri Yachvili as a badly-needed understudy to captain Fabien Galthie) with one eye on the World Cup. Win it, and he cannot be seen to risk forfeiting a tilt at another Grand Slam.
Rarely can a French side have taken such an ominously hardened pack into the Six Nations. The names trip off the tongue. Ibanez, Pelous and Magne have all captained France as have Crenca and Brouzet at club level.
Betsen is a beast and Harinordoquy a sensational number eight. They gave the All Black pack a fearful going over in November.
The only real concern is the absence from the championship of influential Kiwi centre Tony Marsh. Xavier Garbajosa may partner Damien Traille while Aurelien Rougerie is back in the frame. A helluva team, even if less likely to win another Grand Slam.
Player to watch: Vincent Clerc
A 21-year-old flyer having a remarkable rookie season with Toulouse. Joined in the summer from home-town Grenoble in the second division, from where he broke into the French under-21s. Blooded in all three autumn tests, he's also a strong and clever footballer. A real star in the making.
ENGLAND
Coach: Clive Woodward
Capt: Martin Johnson
Grand Slams: 11
Championships: 24
Triple Crowns 21
Affiliated clubs: 1,800
Total players: 548,522
Senior Male Players: 174,000
Forecast: First
After a November to remember, England have France at fortress Twickenham next Saturday and so are odds-on favourites for the championship. Ritualistic slaughters of Italy and Scotland at home will certainly seem anti-climactic then, but, after coming within a win of the grand slam for the last four years running, it's the clean sweep they must have.
There's power and dynamic ball-carriers aplenty up front, while the rebirth of Ben Cohen and emergence of James Simpson Daniel gives Woodward more gamebreakers out wide. However, what to do with Jason Robinson and his midfield combination remain riddles.
Some key forwards are pushing on, though England have the resources to shuffle their hand for five games in seven weeks, while the team is hugely reliant on the remarkable, metronomic goal-kicking, real flair and big hits of the phenomenal Jonny Wilkinson. The evidence of the autumn also underlines the impression that their backs miss Brian Ashton's lateral thinking, and that world record-breaking winning run at Twickenham (now standing at 18) has to end some time.
Player to watch: James Simpson-Daniel
Heaps of good judges rate this guy as the most gifted runner to emerge in England since Jeremy Guscott. Despite being sidelined with glandular fever after a stunning autumnal bow against New Zealand and Argentina, Clive Woodward is keen to integrate the 20-year-old centre-cum-winger before the World Cup.
SCOTLAND
Coach: Ian McGeechan
Capt: Bryan Redpath
Grand Slams: Three
Championships: 14
Triple Crowns: 10
Affiliated clubs: 253
Total players: 68,500
Senior male players: 11,500.
Forecast: Fourth
The manner of Budge Pountney's pre-tournament retirement can't have been ideal, but it is probably the one area where Scotland have most options, with Ross Beattie, Andy Mower and Jon Petrie all in the frame and regular blindside Martin Leslie having played impressively at openside for Edinburgh lately.
Buoyed by autumnal wins over Romania, South Africa and Fiji, if Bruce Douglas nails down the tight head slot then a pack backboned by four Lions (Smith, Bulloch, Murray and Taylor) will cause anyone problems.
A key decision rests between the more dependable Gordon Ross or McGeechan's long-time favourite Gregor Townsend, with the latter reverting to outside centre an obvious option in giving them some badly needed creativity further out.
They're not exactly overladen with match-winners, but they'll be well-organised and well-prepared. Ominously, if they're to spring one surprise then turning over Ireland looks the most plausible. The Scots also have Wales and Italy to come at home, so the opener against Ireland is pivotal as there's not much chance of wins in Paris or Twickenham.
Player to watch: Gordon Ross
Scored 23 points on his debut against Tonga and then, curiously wasn't seen again until the wins over Romania and South Africa a year on. A clever tactician, Ross could be the steadying influence at 10 that Scotland have lacked since Craig Chalmers about a decade ago.
WALES
Coach: Steve Hansen
Capt: Colin Charvis
Grand Slams: Eight
Championships: 22
Triple Crowns: 17
Affiliated clubs: 372
Total players: 57,200
Senior male players: 17,000
Forecast: Fifth
Bizarrely, but typically, there are some strongly optimistic noises emanating from the valleys despite the dismal showing of most of their sides in Europe, not to mention the off-field lack of direction from administrators, the general depression hanging over the game or the failure of any expensive, quick-fix solutions.
To compound a sudden dearth of experience (they have only one Lion in a squad of 30 despite Graham Henry's recent largesse) their two standardbearers in the last few years, Scott Quinnell and Rob Howley, have ridden off into the Llanelli and Wasps' sunsets and such has been the form of Charvis that Neath coach Lyn Jones was overheard to remark: "Is Colin Charvis still playing rugby?"
Granted Steve Hansen has injected some spirit, though being within five points of the All Blacks on a Millennium mudbath entering injury-time probably gave a misleading picture, and if they aren't brought down to ground with a thud in Rome next Saturday, then they assuredly will be a week later when England come to the Millennium Stadium. Fourth would be progress.
Player to watch: Robert Sidoli
Part of the famous Italian ice-cream family, Sidoli could have played for the land of his father, but instead opted for his native Wales. A former Youth, Under-21 and A international, this dynamic, 6' 6", 181/2 stone lock should, ironically, make his Six Nations debut in Rome.
ITALY
Coach: John Kirwan.
Capt: Alessandro Troncon.
Grand Slams: None
Championships: None
Affiliated clubs: 500
Total players: 34,730
Senior male players: 9,000.
Forecast: Sixth
John Kirwin gave youth its head with some experimental selections last autumn and spirit abounded in the 34-3 defeat to Australia after a poor display in the 36-6 defeat to Argentina. But, again, the approach looked too structured for the Italian mindset, which still looks better suited to a more French orientated style.
Despite the emergence of some talented new young backs, those matches underlined Italy's lack of clinicism, and it is now four games against first rank opposition since the Azzurri scored a try - against Ireland last year. Furthermore, the up-and-coming Matteo Barbini and Gonzalo Canale are sidelined, as is Diego Dominguez, which may be no bad thing in the longer-term, so Ramiro Pez will partner Alessandro Troncon.
It is now 14 successive defeats in the Six Nations since they won their innaugural match against Scotland. An opening day mugging of the Welsh seems their best chance, but despite Calviason's win over Neath and some encouraging Euro form, the odds are still against it.
Player to watch: Sergio Parisse
Son of Italian emigrees to Argentina (his father played for L'Aquila), Parisse was 'discovered' by the Italian under-19 squad bound for the World Cup in Chile. Now 19 and with Treviso, Parisse is a raw talent but a natural ball-carrying number eight.