Mary-Kate Olsen @ Calvin Klein Party

Mary-Kate Olsen attends a Calvin Klein party at the University of Westminster on Monday in London, England.

According to Fashion Week Daily, this was the cause for celebration: “Calvin Klein, Inc. collaborated with British artist and 2001 Turner Prize winner Martin Creed on a unique performance project at London’s newly created underground venue P3. As conceived by Creed, the event brought together all of Calvin Klein’s spring collections within his own installations and featured an orchestral element as the simultaneous centerpiece and backdrop of the event. The performance is inspired by Creed‘s “Work 673″ and featured Calvin Klein Collection, ck Calvin Klein, Calvin Klein Jeans, Calvin Klein Underwear, and Calvin Klein Swimwear.”

Pictured below: Francisco Costa, the creative director of Calvin Klein Collection.

10+ pictures inside of MK at the CK par-tay…