Morten Johannes Lauridsen III[1] (born February 27, 1943) is an American composer and teacher. A National Medal of Arts recipient (2007),[2] he was composer-in-residence of the Los Angeles Master Chorale from 1994 to 2001,[3] and is professor emeritus of composition at the USC Thornton School of Music, where he taught for fifty-two years until his retirement in 2019.[4]

Referring to Lauridsen's religious music, the musicologist and conductor Nick Strimple said he is "the only American composer in history who can be called a mystic. Lauridsen's probing, serene work contains an elusive and indefinable ingredient which leaves the impression that all the questions have been answered."[9] From 1993, Lauridsen's music rapidly increased in international popularity, and by the end of the century he had eclipsed Randall Thompson as the most frequently performed American choral composer.

He received a National Medal of the arts, from George Bush in 2007