Stefan Kahil Lessard (born June 4, 1974) is an American musician, most famous as the bassist for the Dave Matthews Band.
Lessard was born in Anaheim, California, to musician Ron and Jacqueline Lessard. After moving a number of times during his childhood, Lessard and his family eventually settled in Charlottesville, Virginia in 1987. They had previously lived from 1980–84 in Buckingham County, Virginia and in Richmond, Virginia from 1984–86.
After moving back to Charlottesville from Madison, Wi. in 1987, he enrolled in the Tandem School, where he studied music under trumpeter John D'earth and bassist Peter Spaar. D'earth and Spaar recommended Lessard to Dave Matthews for inclusion in his new band, which was looking for a bassist. Lessard joined Dave Matthews Band just as it was forming, when he was sixteen years old. Due to his age, he sometimes had to sneak in the back door of the clubs where the band was playing due to prohibitions on persons under 21 entering venues that serve alcohol.