Karl Jenkins (born 1944) is a Welsh musician and composer.

Jenkins began his diverse musical career as an oboe player in the National Children's Orchestra . He went on to study music at University College, Cardiff , and at the Royal Academy of Music. He was known for the bulk of his career as a jazz and rock musician, joining Canterbury progressive rock band Soft Machine in 1972 and leading them for several years.

His most heard piece of music is the classical theme used by De Beers diamond merchants for their famous television advertising campaign focusing on jewelry worn by people who are otherwise seen only in silhouette. He later included it as the title track in a compilation of various works called Diamond Music , and eventually created Palladio, using it as the theme of the first movement.

As a composer, his breakthrough came with the innovative crossover album Adiemus: Songs of Sanctuary (1994), which sold well enough (topping classical album charts) to spawn a series of successors (each revolving around a central theme) including:

• Adiemus II: Cantata Mundi
• Adiemus III: Dances of Time
• Adiemus IV: The Eternal Knot

And a Greatest Hits colletion:

• The Best Of Adiemus

Other works:

• Eloise (opera)
• Imagined Oceans (1998)
• The Armed Man: A Mass for Peace (1999)
• Dewi Sant (2000)
• Diamond Music (1996)
• Requiem Mass (2005)

He was awarded the Order of the British Empire in the New Years Honours list for 2005.