Isabelle Geffroy, born 1 May 1980, known by the pseudonym ZAZ, is a singer from Tours, France, who blends the styles nu jazz, soul and acoustic in her music.

In 2001, she started her singing career in the blues band “Fifty Fingers”. She sang in musical groups in Angoulême, especially in a jazz quintet. She became one of the four singers of Izar-Adatz (Shooting Star), a variety band which consisted of sixteen people with whom she toured for two years, especially in the Midi-Pyrenees and the Basque Country.