Keith A. Knudsen was an American rock drummer, vocalist, and songwriter. Knudsen was best known as a drummer and vocalist for The Doobie Brothers. In addition, he founded the band Southern Pacific with fellow Doobie Brother John McFee. He was posthumously inducted into the Rock and Roll Hall of Fame as a member of The Doobie Brothers in 2020.

Cycles is the tenth studio album by American rock band The Doobie Brothers. The album was released on May 17, 1989, by Capitol Records.