Members:

Adam Gontier
Neil Sanderson
Brad Walst
Barry Stock

Three Days Grace (also known as 3DG or TDG) is a Canadian alternative metal/post-grunge band formed in 1997. The band consists of Adam Gontier, Neil Sanderson, Brad Walst and Barry Stock.

Adam, Brad, and Neil originally formed a band called Groundswell in 1992 during their freshman year of high school. Joe Grant, the fourth member of the band, was there from the beginning, but he left in 1997 to attend law school. The three remained a trio and renamed themselves Three Days Grace, which was a name Brad came up with.
In 2000, the band released a 3 song self-titled demo and relocated from Norwood to Toronto. There, they met producer Gavin Brown, who was formerly a member of the band Big Sugar. Brown helped produce their self-titled debut album, Three Days Grace, which was released in 2003.

Upon completion of the album the band recruited Barry Stock to help on lead guitar to give Adam breathing room on stage and on tour.

The album's lead single, "I Hate (Everything About You)" reached number one on the US Modern Rock and Mainstream Rock charts and number two on the Canadian Rock charts. Their second single "Just Like You" gave the group a second number-one in America and also hit number one on rock charts in Canada.
In 2005, Adam went to rehab for an addiction to Oxycontin at the Toronto rehab center CAMH (Centre for Addiction and Mental Health), which is where many of the songs for One-X were written, including Animal I Have Become, Never Too Late, Pain and a few more.

On March 31 2006, the band released their first single off of their album One-X entitled "Animal I Have Become," which managed to reach number one on both the US Modern Rock and US Mainstream Rock.

The album's second single "Pain" was also released topping the Billboard Mainstream Rock Charts in December of 2006 and the Modern Rock Tracks Chart in February of 2007. "Never Too Late" was released as the third single off of One-X in April of 2006. "Never Too Late" marks their third consecutive #1 single from One-X in the Active Rock charts and their 5th overall consecutive #1 song in their career. As of August 2007, the album has been certified platinum by the RIAA for sales of over one million copies.