Gramm began his musical career in his mid-teens, playing in local bands, eventually becoming front man for the band Black Sheep. In 1976, Gramm auditioned as lead singer with the band that came to be known as Foreigner. He became one of the most successful rock vocalists of the late 1970s and 1980s. His unique vocals have made Foreigner one of Billboard's Top 100 Artists of All Time in hit songs history. Gramm was the lead vocalist on all of Foreigner's hit songs, including "Feels Like the First Time", "Cold as Ice", "Long, Long Way from Home", "Hot Blooded", "Double Vision", "Blue Morning, Blue Day", "Head Games", "Dirty White Boy", "Urgent", "Juke Box Hero", "Break It Up" and "Say You Will". He co-wrote most of the songs for the band, which achieved two of its biggest hits with the ballads "Waiting for a Girl Like You", which spent ten weeks at #2 on the 1981-82 American Hot 100, and "I Want to Know What Love Is", which was a #1 hit internationally (US & UK) in 1985. Their first 8 singles cracked the Billboard Top 20, (4 went Top 10), making them the first group since the Beatles to achieve this in 1980. In 1997, Gramm was diagnosed with a benign brain tumor. The resulting surgery and recovery program affected his stamina and voice. He continued to work throughout his illness and in 1999, was back touring with Foreigner playing summer festivals and smaller markets. Gradually, Gramm's health and energy have rebounded. He left Foreigner again in 2003, and has been touring steadily since January 2004. In May 2013, Gramm’s autobiography, Juke Box Hero: My Five Decades in Rock ‘n’ Roll, was released.