F91 Dudelange is a football club, based in Dudelange, in southern Luxembourg.

Dudelange's team colors are red and yellow vertically-striped shirts, with red shorts and socks.

It was formed in 1991 from the clubs Alliance Dudelange, Stade Dudelange, and US Dudelange. All three clubs had won the National Division or the Luxembourg Cup before, but each had fallen upon hard times, and the amalgamated club was expected to be more stable, in both a sporting and financial sense.

Turning the club into a title-challenging team took a while. Stade Dudelange and US Dudelange had been in Luxembourg's third tier (the National Division), whilst Alliance Dudelange was struggling to remain in the second league (the Division of Honour). The new club would take Alliance's place in the Division of Honour in the 1991–92 season.

F91 was promoted in its first season, and soon established itself as a competent top-flight team, not finishing outside the top half of the table until 1996–97. Towards the end of the 1990s, Dudelange gradually improved, and brought to an end Jeunesse Esch's era of dominance by storming to the 1999–2000 league title by eleven points.

Dudelange (Luxembourgish: Diddeleng, German: Düdelingen) is a commune with city status in southern Luxembourg. It is the fourth-most populous commune, with over 18,300 inhabitants. Dudelange is situated close to the border to France.

As of 2006^[update], the town of Dudelange, which lies in the centre of the commune, has a population of 17,320, making it Luxembourg's third-most populous town. The commune also includes the smaller town of Budersberg, to the north-west. The Mont St. Jean, close to Budersberg, hosts the ruins of a medieval castle.

Dudelange is an important industrial town that grew out of the three villages and a steel mill in 1900. The D in the name of the ARBED steel company, later merged into ArcelorMittal, stood for 'Dudelange.' It is also the site of Dudelange Radio Tower, which is an FM radio and television transmitter.

One of Dudelange's most notable citizens was the Impressionist painter Dominique Lang (1874–1919).

Furthermore Dudelange is home to the most successful Luxembourg football club in recent history. F91 Dudelange won nine national titles in the period 2000 to 2011.

Jeff Strasser (born 5 October 1974 in Mondorf-les-Bains) is a Luxembourgian footballer, who currently manages CS Fola Esch.

As one of the rare successful professional footballers from Luxembourg, Strasser has made a fairly successful career in French and German first divisions. After playing for French side FC Metz in Ligue 1 between 1993 and 1999, he moved to German Bundesliga side 1. FC Kaiserslautern and spent three seasons with the club before leaving it for Borussia Mönchengladbach in 2002. With the two German clubs, he spent seven seasons in Bundesliga and was a regular in each of the seven seasons, making a total of 194 appearances and scoring 10 goals in the league.

In August 2006, he moved to French Ligue 2 side RC Strasbourg. On 31 July 2007, he signed a two-year contract with FC Metz and was released after his contract ended on 30 June 2009, On 17 July 2009, he returned to Luxembourg on 17 July 2009, signing a two-year contract with CS Fola Esch. However, the move only lasted 17 days before Strasser moved to Grasshopper, signing an one-year contract on 15 August 2009.

Guy Hellers (born 10 October 1964) is a Luxembourgian football manager and retired footballer.

He was the head coach of the Luxembourg national team, having succeeded Dane Allan Simonsen in 2004.

In 2010, Hellers resigned as Luxembourg coach and was succeeded by Luc Holtz.

Arguably Luxembourg's most successful player, Hellers shortly played for FC Metz but he spent the majority of his career at Standard Liège, where has been captain. He played 458 matches in total for them, scoring 37 goals. He was surprisingly dismissed by then manager Tomislav Ivic in September 1999 after some verbal clashes between coach and squad.

Hellers made his debut for Luxembourg in an October 1982 European Championship qualification match against Greece and went on to earn 55 caps, scoring 2 goals. He played in 27 FIFA World Cup qualification matches. His final international game was an October 1997 World Cup qualification match against Cyprus.

He scored the only goal in the upset match against the Czech Republic in 1995.