Ospreys share the title of most successful Celtic League side with Irish province Leinster, both having won four titles, indeed in the ten years between 2005 and 2014, only two sides other than Leinster and Ospreys walked away with the crown.
The region, covering Neath and Swansea, also reached the Anglo-Welsh cup final in both 2007 and 2008, gaining revenge on Leicester Tigers in the second final for their defeat in the first.
They have yet to taste glory on the European stage though, the closest they have come being a trio of European Cup quarter-final losses between 2008 and 2010.
Coach Tandy
Steve Tandy is an Ospreys playing legend in his own right having appeared more than 100 times for the region between 2003 and 2010.
In the final years of his playing career he had already begun coaching at the Ospreys age-group teams and won the Welsh Rugby Union Age Grade championships with the regions' Under-16s side.
After retiring from playing be coached Bridgend before moving back to the Ospreys and taking over from Sean Holley as head coach in February 2012.
Tandy won eight of his first ten matches in charge, including the 2012 Celtic League title with a one-point victory over Leinster in the Grand Final.
Shane Williams' late try in his last game for Ospreys took the region to within one point of the Irish province and when Dan Biggar added the extras the title was Tandy's.
It would prove to be the only silverware Tandy has collected thus far, as the following two years they missed out on the Celtic League semi-finals before being beaten 21-18 by Munster in last year's semi-final.
The wait for a trophy will go on for another year as Tandy's side are fighting to break into the top six of the Guinness PRO12 this season.
Greatest season: 2009-10
The third of Osprey's four Celtic League titles was accompanied by one of their best seasons on the continent.
Most notable about the campaign was the introduction of the play-off system to determine the overall Celtic League winner.
Ospreys finished second in the regular season, winning 11 of their 18 games but finishing three points behind Leinster.
The Irish side beat Ospreys twice during the regular season but Scott Johnson's team got the win when it counted.
A final day win over Newport Gwent Dragons gave them a home semi-final tie against Glasgow Warriors.
Tries from Shane Williams and James Hook, as well as two penalties and two conversions from the boot of Dan Biggar, gave Ospreys a comfortable 20-5 win and a place in the final.
Leinster beat their provincial rivals Munster 16-6 in the other semi-final to set up a clash of the top two from the regular season at Dublin's RDS Arena.
First-half tries from Tommy Bowe and Lee Byrne put the visiting Welshman in control of the game and despite four penalties from Jonathan Sexton Ospreys completed the 17-12 win to become the first side to win a hat-trick of Celtic League titles.
In the European Cup Ospreys were knocked out at the quarter-final stage in an agonising one-point defeat at Biarritz.
That came after the pool stage in which they knocked the higher-ranked Leicester Tigers out and Tommy Bowe scored seven tries to be the tournament's leading try scorer.
Greatest XV:
15: Lee Byrne
The flying full-back had a five-year spell with Ospreys during their most successful period in the Celtic League. Just as effective during his sporadic appearances on the win, Byrne impressed coaches so much he was selected as a British and Irish Lion in 2009.
14: Tommy Bowe
The winger is a legend both sides of the Irish sea. Bought over from Ulster in 2008 he had four successful seasons in Wales, becoming the top try-scorer in the 2009-10 European Cup, before moving back to Ulster in 2012.
13: James Hook
An option in any position across the back line, Hook is second in the all-time scoring charts for the region and had the potential to be devastating in broken play.
12: Gavin Henson
The pretty-boy of rugby, he was the Ospreys star both on and off the field and another versatile option that could play anywhere across the back. With a hammer of a kicking boot Henson's undeniable talents on the field often get overlooked for his actions off it.
11: Shane Williams
Quite simply a legend of the game, for Ospreys, Wales and the Lions. He is the record try-scorer for his region and his last-minute effort in the 2012 Celtic League final set up a nerve-shredding title win in his final match.
10: Dan Biggar
Already the record point scorer for his region at just 26, Biggar is metronomic with the boot and almost as effective at racking up the appearances as the points as he approaches the 200 mark.
9: Mike Phillips
Spoiled for choice at scrum-half, Ospreys can boast Mike Phillips, current incumbent Rhys Webb and former All Black Justin Marshall. Phillips gets the nod though for his four-year stint at the Liberty Stadium from 2007, during which he was selected for the 2009 Lions tour.
1: Duncan Jones
Part of the impressively shaggy-haired front row, he was once described by Lyn Jones as his favourite player to coach and is the record appearance holder for Ospreys with 223.
2: Richard Hibbard
A ten-year career with the Ospreys, during which he collected four Celtic League titles, Hibbard played for Ospreys 175 times and scored ten tries, earning his place as starting hooker on the 2013 Lions tour.
3: Adam Jones
Part of the hair bear bunch with his compatriot Duncan Jones, Adam Jones won 95 caps for his country, five for the Lions and four Celtic League titles with Ospreys.
4: Ian Gough
Not afraid to do the dirty work, Gough was part of the glory years at Ospreys, winning two Celtic League titles and helping them to their best ever European performances.
5: Alun Wyn Jones
A one-team man, Jones has been with Ospreys since joining the regional ranks in 2005. Another Osprey to represent the Lions, earning six caps over two tours so far, and looks set to make a double-century of appearances for Ospreys later this season.
6: Ryan Jones
Former Wales and Ospreys skipper whose ten-year career at the region was blighted by injuries. Jones could play across the back row and also at lock, and racked up the trophies with Ospreys, as well as the small matter of three Grand Slams for his nation.
7: Justin Tipuric
Won the Celtic League title in his first year with the region in 2010, then repeated the achievement in 2012. His creativity and vision when running make him far more than a scavenging, flanker at the back of the pack.
8: Filo Tiatia
During five years with Ospreys he made nearly 100 appearances for the region and won two Celtic League titles. The all-action Kiwi became a cult figure with Ospreys fans who appreciated his relentless work rate on the pitch.
To buy tickets for the GUINNESS PRO12 Grand Final click here. Also follow us on Facebook, join the conversation on Twitter, sign up to our YouTube channel for extensive match highlights and sign up for our newsletter for regular updates on the GUINNESS PRO12.
63x46.png){kind=logo}