Lou Gramm (born Lou Grammatico May 2, 1950 in Rochester, New York) is an American rock music vocalist and songwriter, best known as the lead vocalist for the rock band Foreigner, but who also had a successful solo career. Gramm attended Gates-Chili High School in Rochester, New York and graduated with the class of 1968.

Lou Gramm was the drummer with the band Black Sheep when the band, and their 1975 album Encouraging Words, were noticed by Mick Jones who was then looking for a lead vocalist for a new band he was forming. Ultimately Gramm joined the band, and with Foreigner became one of the most successful rock vocalists of the late 1970s until the mid 1980s.

Lou Gramm sang lead vocals on all of Foreigner's hits including the rock songs "Feels Like The First Time", "Cold As Ice", "Hot Blooded", "Urgent", "Double Vision", "Juke Box Hero", "Head Games", "Dirty White Boy" and "Say You Will". The band achieved two of it's biggest hits with the ballads "Waiting For A Girl Like You", which spent ten weeks at #2 on the 1981 American singles charts, and "I Want to Know What Love Is", which was a worldwide #1 hit in 1984.

Lou Gramm and Mick Jones reportedly clashed artistically on several occasions during the lifespan of the band; Gramm wanted the band to remain true to its rock origins and favoured music with a drum and guitar base. Jones meanwhile embraced the 1980s style of synthesiser ballads which proved lucrative.

In 1987, during Foreigner's hiatus, Gramm released the album Ready or Not which brought him positive critical reviews and a top five hit single with "Midnight Blue". This was followed by a 1989 Foreigner album Inside Information and a second solo effort Long Hard Look, which brought a Top Ten hit "Just Between You and Me", and "True Blue Love", which reached the Top 40. Gramm also performed the title song from the 1987 movie The Lost Boys, titled "Lost in the Shadows".

Encouraged by his solo success, and still displeased with the direction Jones was taking Foreigner, Gramm left the group to form Shadow King. The new group's 1991 self-titled album was released by Virgin Records but flopped, and the group shortly disbanded. The same year Foreigner released the album Unusual Heat, a relatively unsuccessful effort fronted by vocalist Johnny Edwards.

Edwards was not widely accepted by the Foreigner fan base and Gramm returned to group in 1992 to record three new songs for the compilation The Very Best of ... and Beyond. In 1994, the group released the album Mr. Moonlight, which, although relatively successful in Europe, had mediocre success in the U.S.

Lou Gramm was invited by Mick Jones to perform backing vocals on a cover version of "I Want to Know What Love Is" he was producing for the Australian singer Tina Arena – this was 1996. The song went on to become a major hit again throughout Europe. In April 1997, on the eve the band was to leave for a Japan tour, Gramm was diagnosed with a type of brain tumor called a craniopharyngioma. Although the tumor was benign, the resulting surgery and recovery program (and damage to his pituitary gland) caused Gramm to gain a lot of weight and it affected his stamina and voice. He continued to work with Jones throughout his illness and in 1999, Gramm was back touring with Foreigner playing summer festivals and smaller markets until the end 2002.

In 2003, Gramm once again split from Foreigner to rejuvenate his solo career with brothers, Ben Gramm and Richard Gramm, and formed the Lou Gramm Band, which at concerts plays all of the old Foreigner hits, and Christian rock.

Lou Gramm and the Lou Gramm Band plans to release an all-Christian rock album.