Dr. Know (born September 15, 1958) is the stage name of Gary Miller, guitarist for Bad Brains, regarded as one of punk rock's most innovative and important bands. Critic Rick Anderson praises Miller's "ability to meld the raw directness of hardcore punk with an almost supernatural virtuosity without sacrificing the power of either approach".
Born in Washington, D.C., Miller has recorded or performed very little outside the group, though he has performed with Mos Def's group Black Jack Johnson. He also performed a solo on the Coheed and Cambria song "Time Consumer" for their first album The Second Stage Turbine Blade and collaborated with the Deftones on Saturday Night Wrist, although his contributions do not appear on the album. He recently made an appearance at the Trocadero in Philadelphia, PA, playing two songs with students from Paul Green's School of Rock Music at the Best of Season show.