Anthony Kiedis - lead vocals Josh Klinghoffer - guitars, bass on track 12, backing vocals, keyboards Chad Smith - drums, percussion Flea (Michael Peter Balzary) - bass (on all songs except track 12), piano, backing vocals

Additional musicians: Brian ‘Danger Mouse’ Burton — Mellotron on track 3; Organ on track 8; Synthesizers on tracks 1, 5, 6, 7, and 13 Elton John - piano on track 6 Mauro Refosco — percussion on tracks 6 and 7 Anna Waronker - additional vocals on track 1 Beverley Chitwood - vocal solo on track 13

All Strings Arranged and Conducted by Daniele Luppi: Score Preparation by Jeremy Levy String Quartet on tracks 2, 4, 11 and 12 was contracted by Chris Tedesco, and includes: Peter Kent — 1st Violin, Sharon Jackson — 2nd Violin Briana Bandy — Viola Armen Ksajikian — Cello

Vocal Choir on tracks 5, 12 and 13 was contracted by SJ Selby, and includes: Beverley Chitwood, Alexx Daye, David Loucks, Kennya Ramsey, Matthew Selby, SJ Selby, Loren Smith, & Gregory Whipple

Recording personnel: Danger Mouse - production Nigel Godrich - mixing engineer

Additional personnel: Kevin Peterson - art direction