Brett W. Gurewitz (born May 12, 1962), nicknamed Mr. Brett, is an American musician, record producer and businessman best known as the guitarist and a songwriter of Bad Religion. He is also the owner of the music label Epitaph Records and a number of sister labels. He has produced albums for Bad Religion as well as Epitaph Records labelmates NOFX, Rancid, and Pennywise, among others. Gurewitz also had a project called Error, which also featured Atticus Ross, Leopold Ross, and Greg Puciato. He is also the co-founder of comic book and graphic novel publisher, Black Mask Studios.