After moving back to Charlottesville from Madison, Wi. in 1987, he enrolled in the Tandem Friends 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.