Lou Koller is an American musician best known as the lead vocalist of the hardcore punk band Sick of It All. Formed in 1986, the band has been influential in the punk and hardcore scenes, known for their energetic performances and socially conscious lyrics. Koller’s powerful voice and stage presence have made him a prominent figure in the genre. In addition to his work with Sick of It All, Koller has collaborated with various artists and bands, contributing to the broader punk rock community. His dedication to music and activism has earned him respect among fans and musicians alike.