A noted session musician, his credits in the studio have included contributions to releases by David Lasley, Tom Scott, and Donna Summer. In 1991, Grillo joined Tower Of Power, appearing on that year's Monster On A Leash set. He spent much of the remainder of the ‘90s performing and recording with them before leaving to pursue other projects. In 1999, Grillo produced long-time Tower Of Power bass player Rocco Prestia's solo debut, Everybody On The Bus, and Grillo would make his own solo debut with Both Sides Of The Coin several years later. ~ Tom Demalon