'Ghosts I–IV' features a wide assortment of musical instruments, including piano, guitar, bass, synthesizer, marimba, tambourine, banjo, dulcimer, and xylophone, with many of these instruments being sampled and distorted electronically. Percussion instruments, contributed primarily by Brian Viglione, were largely constructed out of found objects and house-hold items.

Personnel:
Trent Reznor – performance, production, art direction
Atticus Ross – programming, arranging, production
Alan Moulder – engineering, mix engineering, production
Alessandro Cortini – guitars (4, 11, 17, 20, 24, 28), bass (4), dulcimer (22), additional electronics (19, 22, 29, 33)
Adrian Belew – guitars (3, 4, 7, 10–11, 14, 16, 21, 25, 27, 31–32, 35), electronics (25), marimba (30)
Brian Viglione – drums (19, 22)
Tom Baker – mastering
Rob Sheridan – art direction, photography, visual and physical elements
Artist in Residence – art direction, photography, visual and physical elements
Phillip Graybill – photography
Tamar Levine – additional photography