Ian Underwood played on these albums or songs:

• We're Only In It For The Money (piano, woodwinds)
• Cruising With Ruben & The Jets (piano, alto saxophone)
• Uncle Meat (electric organ, piano, harpsichord, celeste, flute, clarinet, alto saxophone, baritone saxophone)
• Hot Rats (piano, organus maximus, clarinet, saxophone)
• Burnt Weeny Sandwich (keyboards, woodwinds)
• Weasels Ripped My Flesh (alto saxophone)
• Chunga's Revenge - Transylvania Boogie (organ)
• Chunga's Revenge - Road Ladies (rhythm guitar)
• Chunga's Revenge - Twenty Small Cigars (piano)
• Chunga's Revenge - The Nancy & Mary Music (electric piano)
• Chunga's Revenge - Tell Me You Love Me (rhythm guitar, pipe organ)
• Chunga's Revenge - Would You Go All The Way? (electric piano)
• Chunga's Revenge - Chunga's Revenge (electric alto with wah-wah pedal)
• Chunga's Revenge - Rudy Wants To Buy Yez A Drink (electric piano)
• Chunga's Revenge - Sharleena (grand piano, tenor saxophone)
• Fillmore East - June 1971 (woodwinds, keyboards, vocals)
• 200 Motels (keyboards, woodwinds)
• Just Another Band From L.A. (woodwinds, keyboards, vocals)
• Over-Nite Sensation (flute, clarinet, alto saxophone, tenor saxophone)
• Apostrophe(') (saxophone)
• You Can't Do That On Stage Anymore vol 1 - The Florida Airport Tape (keyboards, alto saxophone)
• You Can't Do That On Stage Anymore vol 1 - Once Upon A Time (keyboards, alto saxophone)
• You Can't Do That On Stage Anymore vol 1 - Sofa #1 (keyboards, alto saxophone)
• You Can't Do That On Stage Anymore vol 1 - Let's Make The Water Turn Black/Harry, You're A Beast/The Orange County Lumber Truck (alto saxophone)
• You Can't Do That On Stage Anymore vol 1 - The Groupie Routine (keyboards, alto saxophone)
• You Can't Do That On Stage Anymore vol 1 - Ruthie-Ruthie (keyboards, alto saxophone)
• You Can't Do That On Stage Anymore vol 1 - Plastic People (alto saxophone)
• You Can't Do That On Stage Anymore vol 1 - Sweet Leilani (alto saxophone)
• You Can't Do That On Stage Anymore vol 1 - Oh No (alto saxophone)
• You Can't Do That On Stage Anymore vol 3 - King Kong (keyboards, alto saxophone)
• You Can't Do That On Stage Anymore vol 4 - You Call That Music? (clarinet)
• You Can't Do That On Stage Anymore vol 4 - Tiny Sick Tears (alto saxophone)
• You Can't Do That On Stage Anymore vol 4 - Are You Upset? (alto saxophone)
• You Can't Do That On Stage Anymore vol 5 - Charles Ives (alto saxophone)
• You Can't Do That On Stage Anymore vol 5 - Here Lies Love (alto saxophone)
• You Can't Do That On Stage Anymore vol 5 - Piano/Drum Duet (electric piano)
• You Can't Do That On Stage Anymore vol 5 - Mozart Ballet - Piano Sonata in B flat (acoustic piano)
• You Can't Do That On Stage Anymore vol 5 - Chocolate Halvah (alto saxophone)
• You Can't Do That On Stage Anymore vol 5 - Run Home Slow: Main Title Theme (alto saxophone)
• You Can't Do That On Stage Anymore vol 5 - The Little March (alto saxophone)
• You Can't Do That On Stage Anymore vol 5 - Right There (alto saxophone)
• You Can't Do That On Stage Anymore vol 5 - Where Is Johnny Velvet? (alto saxophone)
• You Can't Do That On Stage Anymore vol 5 - Return Of The Hunch-Back Duke (alto saxophone)
• You Can't Do That On Stage Anymore vol 5 - Trouble Every Day (alto saxophone)
• You Can't Do That On Stage Anymore vol 5 - Proto-Minimalism (alto saxophone)
• You Can't Do That On Stage Anymore vol 5 - My Head? (dialog)
• You Can't Do That On Stage Anymore vol 5 - Meow (alto saxophone)
• You Can't Do That On Stage Anymore vol 5 - Baked-Bean Boogie (alto saxophone)
• You Can't Do That On Stage Anymore vol 5 - Where's Our Equipment? (alto saxophone)
• You Can't Do That On Stage Anymore vol 5 - No Waiting For The Peanuts To Dissolve (alto saxophone)
• You Can't Do That On Stage Anymore vol 5 - A Game Of Cards (dialog)
• You Can't Do That On Stage Anymore vol 5 - Underground Freak-Out Music (alto saxophone)
• You Can't Do That On Stage Anymore vol 5 - German Lunch (dialog)
• You Can't Do That On Stage Anymore vol 5 - My Guitar Wants To Kill Your Mama (alto saxophone)
• You Can't Do That On Stage Anymore vol 6 - The M.O.I. Anti-Smut Loyalty Oath (keyboards, alto saxophone)
• You Can't Do That On Stage Anymore vol 6 - Farther O'Blivion (woodwinds)
• You Can't Do That On Stage Anymore vol 6 - Shove It Right In (keyboards, alto saxophone)
• You Can't Do That On Stage Anymore vol 6 - Lonesome Cowboy Nando (keyboards, saxophone)
• You Can't Do That On Stage Anymore vol 6 - 200 Motels Finale (keyboards, alto saxophone)
• Playground Psychotics (keyboards, alto saxophone, dialog)
• Ahead Of Their Time (alto saxophone, piano)
• The Lost Episodes - Wonderful Wino (saxophone)
• The Lost Episodes - RDNZL (woodwinds)
• The Lost Episodes - Inca Roads (woodwinds)
• The Lost Episodes - Lil' Clanton Shuffle (guitar)
• The Lost Episodes - Sharleena (keyboards, saxophone)