In the mid-nineties Gould began to work as producer and in 1997 he co-produced Faith No More's last record Album of the Year with the former Swans drummer Roli Mosimann. He is now the CEO of Koolarrow Records. In the 1990s Gould sometimes played with the Mexican grindcore band Brujeria. He was also involved in several supergroups, such as Shandi's Addiction (with Maynard Keenan, Brad Wilk and Tom Morello) as well as Black Diamond Brigade (with Norwegian rock musicians Euroboy, Torgny Amdam, Tarjei Strøm and Sigurd Wongraven). Furthermore, he played with Wayne Kramer and Fear Factory, and produced CMX's Vainajala album. His latest musical efforts are a guest appearance on Romanian nu-metal band Coma's new album, due out later this fall, and the production of the new album for the German rock band Harmful, and have also toured with them the whole year 2007. The band is having a break and Billy continues his work back in USA again.
Most recently, Bill has joined up with all star band Fear and the Nervous System, featuring members of Limp Bizkit, Korn, Bad Religion, and others. The first album is due out for release in August 2008.
For most of Faith No More's career, he used a Zon bass, but started with an Aria later on, and can be seen with a Fender Jazz in the music video for Evidence. He began with Peavey amplifiers, then moved to Ampeg amplifiers. He is known for employing a wide variety of playing styles.
Billy Gould will be playing bass in Jello Biafra's new band The Axis Of Evildoers along with Ralph Spight (Victims Family, Freak Accident, Hellworms, etc.) on guitar, and Jon Weiss (Sharkbait, Horsey, Tonnage, etc.) on drums. They made their debut at Jello Biafra's 50th-birthday celebration June 16 and 17, 2008 at the Great American Music Hall in San Francisco.