The Gerry Weber Open is a tennis tournament held in Halle, North Rhine-Westphalia, Germany. Held since 1993, the tournament is played on four outdoor grass courts and is a part of the International Series Tournaments on the ATP Tour schedule.

The Centre Court (the Gerry Weber Stadion) has 12300 seats and a retractable roof which can be closed in 88 seconds so that tennis games can continue with a closed roof when it begins to rain. The stadium is heated and also used for other sport events (handball, basketball, volleyball & boxing) and concerts.

Swiss World Number One Roger Federer has won the Halle tournament four times (2003-06) and holds the record for most singles titles. Federer also won them in consecutive years, and every time Federer won the title, he went on to win the title at the Wimbledon Championships. Federer withdrew from the 2007 tournament, citing fatigue from his loss to no.2 Rafael Nadal in the French Open Men's Final.