[6] Greg Camp formed Smash Mouth in 1994 with Harwell, Kevin Coleman, and Paul De Lisle.

[7] The band's 1999 song "All Star" reached the top 10 in the United States, and it regained popularity after being featured in the 2001 film Shrek.

[11] He performed two songs, "Beside Myself" and "Everything Just Crazy",[citation needed] for the 2013 South Korean–Chinese animated film Pororo, The Racing Adventure.

[13] During a Smash Mouth concert in Urbana, Illinois, on August 27, 2016, Harwell collapsed on stage and was taken by ambulance to a hospital.

[14][15] In August 2020, the band headlined at the Sturgis Motorcycle Rally in South Dakota, with Harwell declaring "Now we're all here together tonight.