String Quartet No. 9 is a chamber music composition by Dmitri Shostakovich, completed in 1964. This work is part of a series of string quartets that showcase Shostakovich's unique style, blending emotional depth with intricate musical structures. The quartet consists of five movements, each varying in tempo and mood. It reflects a range of emotions, from introspective to lively, and is characterized by its use of dissonance and rhythmic complexity. This piece is often noted for its accessibility and is frequently performed in concert settings.