Clubs: VV Ter Leede, AZ Alkmaar (twice), Sky Blue FC, Telstar
• Born in Den Haag, she started playing at the age of six with the boys of SVA Assendelft. Ten years later, at the age of 16, she made here Dutch international debut against Switzerland on 17 August 1997.
• In 2000, at the age of 19, the defender moved to Ter Leede, playing in the Hoofdklasse, then the Dutch top flight, and claiming the double in her first season. After four championships and two KNVB Cups with Ter Leede, she move on to AZ in the summer of 2007 at the start of the newly formed Eredivisie.
• An ever-present in her first two seasons at AZ, and installed as captain, two more league titles followed in 2008 and 2009. She moved to Sky Blue in the United States in March 2010 and after a successful spell returned to AZ. Moved to Telstar for the 2011/12 season after AZ dropped out of the Women's Dutch League. She also took a staff role at the Royal Netherlands Football Association (KNVB) promoting women's football in early 2012.
• Koster made her debut for the Netherlands in 1997, and has won over 100 caps. Her total could have been larger but for a difference of opinion with coach Vera Pauw between January 2005 and October 2007.
• Following her return to the national fold Koster was made captain and led the Netherlands to the semi-finals of UEFA Women's EURO 2009, having qualified for their first major tournament, where they lost to England in extra time.
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