Index is a deluxe hardback collection illustrating the visual language of Steven Wilson by his long-term collaborators Lasse Hoile and Carl Glover. The book covers the period from Porcupine Tree's 2002 album In Absentia up to Steven's fourth solo album Hand. Cannot. Erase from early 2015. The book features an introduction from Steven and an interview in the form of an extended conversation between Lasse and Carl with 240 pages, 340 pictures, (including 178 previously unseen images).