The 2008 Davis Cup was the 97th edition of the most important tournament between national teams in men's tennis. Sixteen teams participated in the World Group and more than one hundred others took part in different regional groups. The first matches were played on February 8–10. The final took place on November 21–23 at Estadio Polideportivo Islas Malvinas, Mar del Plata, Argentina, with Spain beating Argentina 3-1 to clinch their 3rd Davis Cup title.

The eight losing teams in the World Group first round ties, and eight winners of the Group I second round ties entered the draw for the World Group Play-offs. Eight seeded teams, based on the Davis Cup rankings as of 14 April, were drawn against eight unseeded teams.

The Davis Cup is the premier international team event in men's tennis. It is run by the International Tennis Federation (ITF) and is contested annually between teams from competing countries in a knock-out format. The competition began in 1900 as a challenge between Britain and the United States. By 2007, 137 nations entered teams into the competition. The most successful countries over the history of the tournament are the United States (winning 32 tournaments and finishing as runners-up 29 times) and Australia (winning 28 times, including four occasions with New Zealand under the name 'Australasia', and finishing as runners-up 19 times). The present champion is Spain who beat Argentina to claim the title.

The tournament was conceived in 1899 by four members of the Harvard University tennis team who wished to challenge the British to a tennis competition. Once their respective lawn tennis associations agreed, one of the four Harvard players, Dwight F. Davis, designed a tournament format and ordered an appropriate sterling silver trophy from Shreve, Crump & Low, purchasing it from his own funds for about $1000. They in turn commissioned a classically-styled design from William B. Durgin's of Concord, New Hampshire, crafted by the Englishman Rowland Rhodes. Davis went on to become a prominent politician in the United States in the 1920s, serving as US Secretary of War from 1925–29 and as Governor-General of the Philippines from 1929–32.

Roger Federer (German pronunciation: [ˈfeːdəʁɐ]) (born 8 August 1981) is a Swiss professional tennis player who held the ATP No. 1 position for a record 237 consecutive weeks from 2 February 2004 to 18 August 2008. Federer has occupied the #1 ranking for 285 overall weeks, one week short of the record 286 weeks held by Pete Sampras. As of 28 May 2012, he is ranked World No. 3. Federer has won a men's record 16 Grand Slam singles titles. He is one of seven male players to capture the career Grand Slam and one of three (with Andre Agassi and Rafael Nadal) to do so on three different surfaces (clay, grass, and hard courts). He is the only male player in tennis history to have reached the title match of each Grand Slam tournament at least five times and also the final at each of the nine ATP Masters 1000 Tournaments. Many sports analysts, tennis critics, and former and current players consider Federer to be the greatest tennis player of all time.

Federer has appeared in an unprecedented 23 career Grand Slam tournament finals, including a men's record ten in a row, and appeared in 18 of 19 finals from the 2005 Wimbledon Championships through the 2010 Australian Open, the lone exception being the 2008 Australian Open. He holds the record of reaching the semifinals or better of 23 consecutive Grand Slam tournaments over five and a half years, from the 2004 Wimbledon Championships through the 2010 Australian Open. At the 2012 Australian Open, he reached a record 31st consecutive Grand Slam quarterfinal. During the course of his run at the 2012 French Open in Roland Garros, Federer eclipsed Jimmy Connors long standing record of 233 match wins in Grand Slam tournaments when he defeated Adrian Ungur in a second round match.

Andrew Stephen "Andy" Roddick (born August 30, 1982) is an American professional tennis player and a former World No. 1. He is currently the third highest-ranked American player, behind Mardy Fish and John Isner.

He became a Grand Slam singles champion when he won the title at the 2003 US Open, defeating Juan Carlos Ferrero in the finals, which currently makes him the last North American male player to win a grand slam singles event. Roddick has reached four other Grand Slam finals (Wimbledon in 2004, 2005 and 2009, and the US Open in 2006), losing to Roger Federer each time. He is married to Brooklyn Decker, a Sports Illustrated swimwear model and actress.

Roddick was born in Omaha, Nebraska to Jerry and Blanche Roddick. Roddick's father was a businessman and his mother was a school teacher. She now directs the Andy Roddick Foundation. Roddick has two older brothers, Lawrence and John (All-American tennis player at University of Georgia (1996–98) and head tennis coach at the University of Oklahoma), who were both promising tennis players at a young age.

Rafael "Rafa" Nadal Parera (Catalan: [rəˈfɛɫ nəˈðaɫ pəˈɾeɾə]; Spanish: [rafaˈel naˈðal paˈɾeɾa]) (born 3 June 1986) is a Spanish professional tennis player and a former World No. 1. As of 28 May 2012 (2012 -05-28)^[update], he is ranked No. 2 by the Association of Tennis Professionals (ATP). He is widely regarded as one of the greatest players of all time; his success on clay has earned him the nickname "The King of Clay", and has prompted many experts to regard him as the greatest clay court player of all time.

Nadal has won ten Grand Slam singles titles, including a record six French Open titles (tied with Bjorn Borg), the 2008 Olympic gold medal in singles, a record 21 ATP World Tour Masters 1000 tournaments, and also was part of the Spain Davis Cup team that won the finals in 2004, 2008, 2009 and 2011. He completed the Career Grand Slam by winning the 2010 US Open, being the seventh player in history, and the youngest in the open era, to achieve it. He is the second male player to complete the Career Golden Slam (winner of the four grand slams and the Olympic Gold medal) after only Andre Agassi.