The Organ Concerto, Op. 7 is an organ concerto by Icelandic composer Jón Leifs. Its origins go back to 1917, when Leifs was just 18, and was completed in 1930. It is an uncompromisingly dark work somewhat linked to medieval music, with influences from the tvísöngur tradition in a dissonant triadic context. It lasts about 21 minutes, and contains three movements, with a short introduction and finale framing a much longer Passacaglia consisting in thirty variations. Its theme comprises the total chromatic, critic Alex Ross described as Bach walking in the tundra.