Tennis in Belgium is governed by the Royal Belgian Tennis Federation, which is split into the French-speaking AFT and the Dutch-speaking VTV. Belgium is well known in tennis for the two champions Justine Henin and Kim Clijsters, who were both WTA World No. 1 ranked player in the 2000s. Both players also retired respectively in 2007 and 2008, before they came back to the competition respectively in 2009 and 2010. Clijsters won 41 WTA titles, including three US Open titles and the Australian Open in 2011. Henin won 43 WTA titles, including seven Grand Slam titles (four French Open titles, two US Open titles and the 2004 Australian Open), and a gold medal at the 2004 Summer Olympics.