Sleep is an American doom metal power trio from San Jose, California. Sleep earned critical and record label attention early in its career. Critic Eduardo Rivadavia describes them as "perhaps the ultimate stoner rock band" and notes they exerted a strong influence on heavy metal in the 1990s. However, conflict with its record company contributed to Sleep's breakup by the end of the decade. The band reformed in 2009, and has played sporadic live dates internationally since. As of November 2017 there was a message in Morse code posted from the band stating that they almost finished recording material for a new album.