Xabier "Xabi" Alonso Olano (born 25 November 1981 in Tolosa, Spain) is a Spanish footballer who plays for Spanish club Real Madrid and the Spanish national team. He is a central midfielder, often playing as a deep-lying playmaker. He is known for his vision, ability to read the game and delivering long-distance passes.

Alonso began his career at Real Sociedad, and after a brief loan period at SD Eibar returned to the La Liga club. John Toshack appointed Alonso as his team captain and Alonso succeeded in the role, taking Real Socieded to second place in the 2002–03 season. The Spaniard moved to Liverpool in August 2004 for £10.5 million. He won the UEFA Champions League in his first season at the club. The following season he won the FA Cup, and subsequently also the FA Community Shield. He moved to Real Madrid for the start of the 2009–10 season, in a deal worth around £30 million.

Internationally, Alonso has represented Spain in the Euro 2004, Euro 2008 tournaments and the 2006 World Cup. He made his international debut in April 2003 in a 4–0 victory against Ecuador. He won the Euro 2008 tournament with Spain.