Cornerstone is the ninth studio album by Styx, released in 1979. Cornerstone was Styx's follow-up to their second consecutive Top 10 selling Triple Platinum album in a row, 1978's Pieces of Eight. Like the four previous Styx albums, the band produced the album themselves. The band started using a new recording studio Pumpkin Studios in Oak Lawn, Illinois. The album was the first where the band shied away from the art-rock/prog-rock influences that dominated their first eight studio albums and was the band's first move towards a more pop/rock direction. Dennis DeYoung had two ballads on the album. The first was the album's first single and Styx's only US #1 single "Babe" which Dennis wrote for his wife Suzanne. The track was performed and recorded as a demo with just him and the Panozzo brothers but then James Young and Tommy Shaw heard the track and decided to put it on Cornerstone with Shaw overdubbing a guitar solo in the song's middle section. Another ballad was the power ballad "First Time" which was intended to be Cornerstone's second single until Shaw complained and threatened to leave the band.