Leinster Rugby, usually referred to simply as Leinster, is one of the four professional provincial rugby teams from Ireland. They compete in the RaboDirect Pro12 and the Heineken Cup. The team represents the IRFU Leinster Branch, which is one of four primary branches of the IRFU and is responsible for rugby union throughout the province of Leinster. The province plays in blue and white and the crest is in the form of a harp. Leinster's traditional home ground was Donnybrook Stadium, in Dublin 4 although the majority of home games are now played at the RDS Arena. More important games are played in the Aviva Stadium.

Leinster turned professional along with the teams representing the other Irish provinces in 1995 and has competed in the Celtic League since it was founded in 2001, having previously competed in the annual interprovincial championship. Leinster A competes in the British and Irish Cup. Leinster has twice been Celtic League champions and three times been Heineken Cup winners.

On 19 May 2012 Leinster won a record third Heineken Cup in four years with a 42-14 win over Ulster Rugby in the first final to feature two teams from Ireland. Leinster is currently ranked 1st place in the ERC European Rankings.

Leinster (/ˈlɛnstər/ — Irish: Laighin / Cúige Laighean — pronounced [ˈl̪ˠaːjɪnʲ]) is one of the Provinces of Ireland situated in the east of Ireland. It comprises the ancient Kingdoms of Mide, Osraige and Leinster. Following the Norman invasion of Ireland, the historic fifths of Leinster and Mide gradually merged, mainly due to the impact of the Pale, which straddled both, thereby forming the present-day province of Leinster. The ancient kingdoms were shired into a number of counties for administrative and judicial purposes. In later centuries, local government legislation has seen further sub-division of the historic counties. In modern times, clusters of counties have been attributed to certain provinces but these clusters have no legal status. The province itself, while enjoying common usage and forming a strong part of local identity, has no official function for local government purposes. The population of Leinster is 2,501,208 according to the 2006 census, making it the most populous province in the country. The traditional flag of Leinster features a golden harp on a green background.

Isakeli Nacewa (born 22 July 1982 in Auckland, New Zealand) is a New Zealand-born rugby union footballer of Fijian descent. He is a utility back and represents Leinster Rugby in the RaboDirect Pro12 and Heineken Cup competitions. He previously represented the Blues in the Super Rugby competition and Auckland in the Air New Zealand Cup. He has also represented Fiji at international level.

One of the stand-out players for Auckland in their 2005 NPC-winning season, Nacewa is a speedy and versatile player who can play as an outside back or centre. He also proved that he can play as a first five-eighth when he covered successfully for the injured Luke McAlister during the 2006 Super 14 season.

Born and raised in New Zealand, Nacewa qualified to play for Fiji through his ancestral links. He was included in Fiji's squad for the 2003 Rugby World Cup and came on as a substitute against Scotland. In 2006, he quit the Fiji national team as he wanted his eligibility changed from Fiji to New Zealand. But due to IRB law, his appearance for Fiji in the World Cup made him ineligible for the All Blacks, Nacewa considered legal advice to persuade the IRB to annul his Fiji cap, however the IRB has since ruled that Nacewa is a Fijian citizen and has played for Fiji during the 2003 Rugby World Cup, making him only eligible to play for Fiji. According to media reports in October 2009, Nacewa was sounded out about the possibility of again playing for Fiji on their tour to Europe, but he rebuffed these approaches to retain his focus on club rugby with Leinster.

Brian Gerald O'Driscoll (born 21 January 1979) is an Irish professional rugby union player. He is the current captain of the Ireland Rugby team and captained Leinster Rugby until the start of 2008 season. He also captained the British and Irish Lions for their 2005 tour of New Zealand. Registered at University College Dublin RFC, he plays at outside centre for the Irish provincial team Leinster. O'Driscoll was chosen as Player of the Tournament in the 2006, 2007 and 2009 RBS Six Nations Championships.

O'Driscoll has 123 Test caps, 117 for Ireland (80 as captain), and 6 for the British and Irish Lions. He has scored 45 tries for Ireland and 1 try for the Lions in 2001, making him the highest try scorer of all time in Irish Rugby. He is 8th-highest try scorer in rugby union history, and the highest scoring centre of all time. O'Driscoll holds the Six Nations record for most tries scored with 25. He has scored the most Heineken Cup tries (30) for an Irishman. He is widely regarded as one of the best centres to have played the game.

Robert Kearney (born 26 March 1986), also referred to as Rob Kearney, is an Irish rugby union footballer who currently plays for UCD, Leinster and Ireland. As a youth he also played rugby union for Clongowes Wood College and Gaelic football for Louth in the All-Ireland Minor Football Championship.

Born and raised in the Cooley Peninsula, Kearney, like many of his peers, got involved in athletics at an early age. The dominant sport in the area is Gaelic football. As a youth, Kearney played Gaelic for Naomh Mhuire, and in the Cooley Kickhams underage setup, before graduating to the Cooley senior football team at the relatively young age of 16. He played for Cooley in the Louth Senior Football Championship final in 2004.

Kearney attended Clongowes Wood College in County Kildare for his secondary education. After his Leaving Certificate he moved to University College Dublin, where he studied Arts. He graduated in April 2010 with a Bachelor of Arts degree.

Kearney attended University College Dublin where he played for the rugby team. In 2005 he helped the U-20s team win the McCorry Cup, beating Trinity College in the final.