Mo Bros, supported by their Mo Sistas, start Movember (November 1) clean shaven and then have the remainder of the month to grow and groom their moustache.
During Movember, each Mo Bro effectively becomes a walking billboard for men's health and, via their Mo, raises essential funds and awareness for Movember's men's health partner - Action Prostate Cancer, Irish Cancer Society - before the shave-off at the end of the month.
The idea for Movember came about in 2003 when a few mates were having a beer in a small bar in Melbourne, Australia. Inspired by the women's health movement, it was recognised that men were lacking a way to engage and actively involve themselves in their own health.
During a conversation about fashion and past trends, the idea came up to bring the moustache back for one month, and in doing so, have some fun, raise a small amount of money and hopefully encourage men to talk about their health with each other.
Since this time, Movember has continued to grow each year, both in terms of participation numbers and funds raised.
In its first year, 30 Mo Bros took part in Movember and last year, across the globe more than 173,000 Mo Bros and Sistas got on board, raising more than €14 million across the Movember's men's health partners globally.
Within the Ireland squad, there has been plenty of freshly-grown facial hair sprouting up in the last number of weeks. You can help support Movember by donating money in recognition of some of the players' efforts.
Three of players in the squad to play South Africa - Jamie Heaslip, Cian Healy and Tony Buckley - have their own Movember donation pages.
Please give what you can to support this worthy cause, and in the words of Ireland's number 8, 'let's get the push on!'
FLASHBACK - NOVEMBER 11, 2006 - IRELAND 32 SOUTH AFRICA 15: Ireland signalled their intent for the season ahead as they ran four classy tries past South Africa to send Jake White's men spiralling out of a windswept Dublin.
Eddie O'Sullivan's Irish side ran riot in the first half to launch the GUINNESS Test Series with a crushing 32-15 victory over South Africa.
The win was only Ireland's third in 18 meetings with the 'Boks, following on from the successes in 1965 and 2004.
The Triple Crown holders, with a settled line-up, entered the match as red-hot favourites and fully justified the tag with a blistering display that cut the outclassed 'Boks to pieces. Tries from Andrew Trimble, David Wallace, Marcus Horan and Shane Horgan did the damage.
At times in the first half they looked unstoppable with Trimble, Horgan, Gordon D'Arcy and captain Brian O'Driscoll turning on the style to leave the understength visitors chasing shadows.
Ronan O'Gara controlled the game to good effect from out-half and kicked 12 points, while up front, the monster touring pack was dismantled by the Irish.
The home side found less space in the second half, which saw Francois Steyn and Bryan Habana dot down for South Africa, but they were already out of sight before Horgan's late try gift-wrapped the result.
South Africa wore replicas of their original 1906 jersey, with no sponsor's logo, to commemorate a centenary of Springbok rugby, but it was not a performance to honour their proud history.
In two personal milestones, skipper John Smit equalled Gary Teichmann's record of 36 games as captain and also became the first Springbok to make 40 consecutive appearances.
But otherwise the 28-year-old Sharks hooker - the only survivor from the 17-12 defeat in Dublin two years ago - will want to forget his side's performance as quickly as possible.
The Springboks' experimental line-up - coach White left ten first choice players at home - included three new caps in Bevin Fortuin, Jaco Pretorius and Steyn.
Try-machine Habana played his first Test match at outside centre and Ireland took full advantage of their opponents' lack of experience.
It looked very different at the start, however, as breaks from Fortuin and Ricky Januarie swept South Africa deep into Irish territory before Andre Pretorius missed with a drop goal.
But the Cats number 10 made amends by nailing a penalty moments later as the tourists capitalised on their impressive opening - only to then concede the opening try.
Ireland surged forward and won a scrum 10 metres out, which they used to bring Trimble in from the left wing and the powerful Ulsterman burst through the Springbok midfield and crossed close to the posts. O'Gara converted to give the home side a 7-3 lead.
South Africa set off on a 10-metre rolling maul in the 18th minute but Pretorius knocked the ball on and Ireland capitalised with a huge kick from O'Gara that pinned the tourists back close to their line.
Pretorius attempted to clear from the lineout but only found Trimble, who set up a promising move which was halted when O'Gara ran back into the forwards. The Munster out-half had won a penalty, however, which he sent between the uprights.
Trimble began the move that led to Ireland's second try in the 24th-minute, with the Ulster winger breaking through several tackles before recycling.
Quick hands saw the ball spun right where Ireland had numbers and Horgan drew his man before supplying the scoring pass to flanker Wallace, who raced in behind the posts.
Ireland should have added their third try shortly afterwards but Horgan opted to go it alone even though D'Arcy had looped around him and was available for a pass.
D'Arcy, who claimed the man-of-the-match gong, was making ground in the midfield and one lung-busting run from Paul O'Connell drew a mighty roar from the Lansdowne faithful.
Stormers centre Jean de Villiers relieved the pressure by shrugging off a tackle from O'Gara and he made 30 yards before being hauled to the ground.
South Africa went on to win a five-metre scrum, but number 8 Pierre Spies was smashed to the ground by Wallace and Denis Leamy when he broke from the back of the set-piece and Ireland were awarded a penalty.
Horgan powered through Habana as the Irish staged a fresh attack which nearly resulted in a try for Trimble in the corner.
Some desperate cover defence from Jaco Pretorius kept him out but the ball was kept alive and Munster prop Horan surged over from close range, with O'Gara converting for a 22-3 buffer.
D'Arcy nearly threaded his way through as Ireland raced out of the blocks for the second half, but South Africa won a turnover and prop CJ van der Linde made an unlikely clearance with his right boot.
Pretorius missed a long range penalty as his miserable evening continued and Trimble threatened in the left corner only for referee Paul Honiss to rule O'Driscoll's pass forward.
Ireland maintained the pressure, however, with Horgan charging into space and O'Gara taking the move on until Honiss penalised South Africa for interfering at the breakdown.
O'Gara landed the subsequent penalty and when Pretorius kicked the ball out on the full, Ireland were able to launch a fresh attack which was stopped when Horgan was hauled down.
Ireland, though, were at panic stations when Danie Roussouw burst through and Steyn crossed in the corner.
Habana showed his finishing skills to their fullest with a remarkable solo try, but Ireland crushed any fightback hopes the 'Boks had with a late try from Horgan, brilliantly teed up by a maurading run from Girvan Dempsey and a lovely inside pass from O'Driscoll. O'Gara converted to complete a memorable victory.
IRELAND: Girvan Dempsey; Shane Horgan, Brian O'Driscoll (capt), Gordon D'Arcy, Andrew Trimble; Ronan O'Gara, Peter Stringer; Marcus Horan, Rory Best, John Hayes, Donncha O'Callaghan, Paul O'Connell, Neil Best, David Wallace, Denis Leamy.
Replacements used: Simon Easterby for N Best (61 mins), Geordan Murphy for Trimble, Bryan Young for Horan (both 67), Isaac Boss for Stringer (75), Paddy Wallace for O'Gara, Malcolm O'Kelly for O'Connell, Frankie Sheahan for R Best (78).
SOUTH AFRICA: Bevin Fortuin; Jaco Pretorius, Bryan Habana, Jean de Villiers, Francois Steyn; Andre Pretorius, Ricky Januarie; Lawrence Sephaka, John Smit (capt), CJ van der Linde, Johan Ackermann, Albert van den Berg, Danie Rossouw, Juan Smith, Pierre Spies.
Replacements used: Ruan Pienaar for Januarie (4-8 mins, blood), BJ Botha for Sephaka (half-time), Johann Muller for Ackermann (53), Jacques Cronje for Rossouw, Wynand Olivier for J Pretorius (both 73). Not used: Chiliboy Ralepelle, JP Pietersen.
Referee: Paul Honiss (New Zealand)
EUROPE'S TOP SPOT UP FOR GRABS IN RANKINGS: There could be some notable shifts in the IRB World Rankings after the final weekend of autumn internationals is done and dusted.
France and Ireland go into the weekend separated by mere thousandths of a rating point in the battle for the mantle of the leading northern Hemisphere nation.
Les Bleus have already beaten New Zealand once this year in Dunedin and upset World champions South Africa in Toulouse a fortnight ago, a result which saw the All Blacks return to the summit of the IRB World Rankings.
The last time France met New Zealand in Europe was in the quarter-finals of Rugby World Cup 2007 when France ended New Zealand hopes with a 20-18 victory in Cardiff, so the All Blacks will be eager to banish those painful memories.
If the All Blacks want to remain unbeaten on this tour and keep hold of that number one ranking they must win in Marseille, because even a draw will see them swap places with the Springboks if they win in Ireland.
New Zealand and South Africa will not end 2009 outside of the top two, such is their present cushion over the nations below them. However both will be eager to finish the year on top of the IRB World Rankings.
Three years have passed since Ireland and South Africa last locked horns, the home side having run out 32-15 winners at Lansdowne Road on that occasion and another success would cap a year to remember for Declan Kidney's side.
If Ireland make it three wins in-a-row against the Springboks then they can reclaim the mantle of leading northern Hemisphere nation, provided Les Bleus lose or the Irish triumph by more than 15 points and France do not.
Notably, Australia's first loss to Scotland in 27 years last weekend has seen their cushion over France and Ireland slashed to just under eight tenths and put their third place in the rankings under serious threat.
If Wales repeat their 21-18 success of 12 months ago and France beat New Zealand or Six Nations champions Ireland beat Tri Nations winners South Africa, then Robbie Deans' Wallaby side will surrender that third spot.
Click here to view the current IRB World Rankings.
"We haven't been thinking a whole lot about it, because we had big internationals against Australia and Fiji. But as soon as the Fiji game, straight away you begin to think, yeah, everyone starts putting it (the South African game) in that bracket - we won the Six Nations and they won the Tri Nations.
"It's a massive game, but you just have to take it as another international. If you kinda put extra pressure on yourself with captions like that, you can make it probably more than it is.
"It's another international game that we have to go out and perform in."
Ireland lock Donncha O'Callaghan comments on Saturday's game being billed as the northern Hemisphere champions versus the southern Hemisphere champions
"They played in Toulouse, not a lot of teams come out of there with a victory. They beat Italy well - New Zealand did struggle against Italy. Based on their last game, (South Africa) are in good form.
"They work to their strengths. They've a good kicking game, they rely on that a lot. And they've got a good strong forward base and set piece. We know where they are going to come at us.
"From our perspective, we have a fair bit of intellectual knowledge there from a lot of guys who were involved in that (Lions) series, and we've tapped into that.
"Obviously we've got Gert (Smal), who was there with South Africa for a number of years, and we've tapped into that knowledge. But none of it guarantees us antything, it's just knowledge and knowing something.
"We've a lot of work to do this week to make sure we front up where we need to front up.
"We've had two Tests so far this campaign and things have moved in a good direction for us, but we'd like to finish off strongly - that's for sure."
- Ireland defence coach Les Kiss gives his take on Saturday's GUINNESS Series Test against the Springboks at Croke Park
"I would see Ireland as a very well balanced team that can play any type (style) of game - especially against Australia they played very well and moved the ball at the right times, but they are also capable of playing a tactical game inspired by good use of the boot.
"We figured it would be (Ronan) O'Gara at number 10 for them but we were also aware that (Jonathan) Sexton was a contender.
"By all accounts he played very well against Fiji and his presence will make it a little more difficult for us because we don't have much information on him and don't know what he is capable of.
"It's probably a big boost to Ireland because they would now appear to have two great out-halves."
- South Africa scrum half Fourie du Preez, a nominee for the 2009 IRB Player of the Year award, gives his opinion on the Ireland team ahead of this weekend's crunch tie
25 - Tommy Bowe will chalk up a quarter-century of Ireland caps when he dons the number 14 shirt against South Africa in Saturday's clash at Croke Park. Bowe, who produced some eye-catching displays during the Lions tour, has scored six tries in his last nine appearances for Ireland
3 - The number of nominees for the 2009 IRB Player of the Year award who will be on the pitch come kick-off time at Croke Park on Saturday. Ireland's Brian O'Driscoll and Jamie Heaslip are in the running for the gong, as is South African number 9 Fourie du Preez
11 - This will be Test number 11 for Ireland at Croke Park. The men in green have won six of their ten games to date at the Jones's Road venue - beating England (2), Italy, Scotland, Argentina and France - with defeats also to France, Wales and New Zealand, and a draw last time out against Australia
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