Bonded by Blood is the debut album by the San Francisco thrash metal band Exodus. Although the album was completed in the summer of 1984, it was not released until 1985 due to issues with Exodus and its record label. It is considered one of the most influential thrash metal albums of all time, utilizing the solo trade-off method which will later become a staple of many thrash and death metal songs. It is also the only full length studio album of Exodus to feature Paul Baloff on vocals, though he was also on their 1982 Demo.
The original album cover art was an illustration of good and evil co-joined twin infants. For the 1989 reissue this cover was replaced with the band logo on a red-and-black image of a crowd. The album was remastered and re-issued by Century Media in 1999 in Europe only, with two live tracks from its Combat re-release in 1989, featuring Steve Souza on vocals. This reissue from Century Media restored the original twin cover artwork.
In 2008, the album was re-recorded with the band's modern line-up as Let There Be Blood. Guitarist Gary Holt and drummer Tom Hunting are the only band members to play on both the original and the re-make.