In 1997 Naoko won 1st Prize at the ARD International Music Competition in Munich, becoming the first violist in 21 years to win this prize. She has been a welcome guest at international concert venues ever since. Prior to that she won the International Competition in Geneva in 1996 as well as winning 1st Prize at the International Instrumental Competition in Markneukirchen, Germany in 1995. In 1998 she won the Young Concert Artist International Auditions in the United States.
Ms. Shimizu has performed as soloist with such orchestras as the Symphonieorchester des Bayerischen Rundfunks, the SWR Radio-Sinfonieorchester Stuttgart, the Orchestre de la Suisse Romande, the Budapest Strings at the Rheingau Musik Festival as well as with many Japanese orchestras. She has also appeared in recital on solo concert tours of the US, Italy and Japan.
As a passionate chamber musician she was invited to, among others, the Lockenhaus Music Festival, the Marlboro Music Festival, and also played Viola Quintets with the Emerson String Quartet and the Tokyo String Quartet.
She has been the principal violist of the Berlin Philharmonic since 2001 as well as being in high demand as a soloist and a chamber musician.