Picker has also composed numerous chamber works. In 2009, the American String Quartet commissioned and premiered his "String Quartet No. 2" at Merkin Concert Hall in New York. In that same year, the pianist Ursula Oppens premiered Picker's "Four Etudes for Ursula" and "Three Nocturnes for Ursula" at Baisly Powell Elebash Recital Hall, also in New York. In 2011, Picker was featured in a Miller Theatre "Composer Portrait" Concert, featuring the Signal Ensemble, Sarah Rothenberg, and the Brentano String Quartet, who premiered his "Piano Quintet" "Live Oaks".