When she was a young child her family moved to Los Angeles, California, where she started studying violin at the age of three and a half using the Suzuki method.
[2] When Leila was 13 the Josefowiczes moved to Philadelphia so she could attend the prestigious Curtis Institute of Music, where she studied with Jaime Laredo, Jascha Brodsky, Felix Galimir and Joseph Gingold.
Josefowicz made her Carnegie Hall debut in 1994 performing the Tchaikovsky Concerto with Sir Neville Marriner and the Academy of St. Martin in the Fields.
Josefowicz has kept a busy international schedule as a soloist, performing regularly around the world, including North and South America, Europe, Asia, Australia and New Zealand.
Josefowicz is acclaimed for championing new compositions,[citation needed] including works by John Adams, Oliver Knussen, Thomas Adès, and Luca Francesconi.