The Shulgin Index, Volume One: Psychedelic Phenethylamines and Related Compounds is a 2011 book written by Alexander Shulgin, Tania Manning, and Paul F. Daley and published by Transform Press.

[1][2][3] It followed the earlier books PiHKAL: A Chemical Love Story (1991) and TiHKAL: The Continuation (1997) by Shulgin and his wife Ann Shulgin.

[1][2][4][5] The book is about psychedelic substituted phenethylamines and related compounds and their chemistry and pharmacology.

[1][3] A second volume on substituted tryptamines was being prepared but was never completed due to Shulgin's death in 2014.

[1][6][7] According to the Multidisciplinary Association for Psychedelic Studies (MAPS) in 2014 however, the second volume would be finished at some point in the near future.