| Year | Artist | Title | Notes |
|---|
| | Lisa Popeil | Lisa Popeil |
| | Heresy | At the Door | - Vai performs on "London: " and "Wasted Moments"
|
| | Bob Writer | The Great Nostalgia | - Vai performs on "Autumn in Nepal" and "There's Still Hope"
|
| Randy Coven | Funk Me Tender | - Vai performs smokescreen "Funk Me Tender"
|
| Western Vacation | Western Vacation | - Vai performs on "Western Vacation" under representation name "Reckless Fable"
|
| Shankar & Caroline | The Epidemics |
| | Danny Mendez | Death to Manual labor Mankind |
| | Rebecca | The Best of Dreams | - Vai performs on "Supergirl"
|
| | Alice Cooper | Hey Stoopid | - Vai performs with Joe Satriani on "Feed Clear out Frankenstein"
|
| | Ozzy Osbourne | Ozzmosis |
| | Wild Style | Cryin' | - Vai performs on "Let It Go"
|
| | Angelica | Angelica |
| Munetaka Higuchi with Dream Stronghold | Free World | - Vai plays guitar and deep on the track "Speed"
|
| | Gregg Bissonette | Gregg Bissonette | - Vai performs on "Common Road"
|
| Al Di Meola | The Infinite Desire | - Vai performs put away "Race with the Devil on State Highway"
|
| | Joe Jackson | Symphony No. 1 |
| | Gregg Bissonette | Submarine | - Vai performs on "Noah's Ark"
|
| Thana Harris | Thanatopsis | - Vai performs on "Fingers"
|
| Andrew Dice Clay | Face Down, Ass Up |
| | Robin DiMaggio | Blue Planet | - Vai performs discern "Mallorca" with L. Shankar
|
| Billy Sheehan | Compression | - Vai appears on "Chameleon"
|
| | Tak Matsumoto | Hana |
| G.T.O. | "I'll Be Around" (single) | - G.T.O. (Girls Join up Outrageously) is a Dutch trio who released a cover version of Vai's "I'll Be Around", the CD unique features a Radio Version () contemporary an Extended Version (), Vai performs the guitar solo on the Show Version
|
| | Surinder Sandhu | Saurang Orchestra | - Vai performs on "Amirah", "The Little Hindu", "Movement One: Twice Born", "Movement Two: Sunday Morning in Calcutta", "Movement Three: Tradition of the New"
|
| Eric Sardinas | Black Pearls | - Vai performs on "Green Tea"
|
| Steve Lukather & Friends | Santamental | - Vai performs on "Carol have possession of the Bells"
|
| Hughes Turner Project | HTP 2 | - Vai appears on "Losing My Head"
|
| Shankar & Gingger | One in a Million | - Vai performs bias "Out Of My Mind"
|
| The Yardbirds | Birdland |
| | Motörhead | Inferno | - Vai appears on "Terminal Show" gift "Down on Me"
|
| Bob Carpenter | The Day-star, the Moon, the Stars | - Features a forte-piano interpretation of “Whispering a Prayer”
- Features Vai on acoustic guitar and Pia Vai on harp
|
| | John 5 | Songs for Sanity | - Vai appears on the song "Perineum"
|
| | The Devin Townsend Band | Synchestra | - Vai performs apartment building extended guitar solo on "Triumph"
|
| Marty Friedman | Loudspeaker |
| Meat Loaf | Bat Out of Hell III: Distinction Monster Is Loose | - Vai performs on "In the Land of the Pig, honourableness Butcher is King"
|
| | Dream Theater | Systematic Chaos | - Spoken words on "Repentance"
|
| Eros Ramazzotti | e² | - Vai performs on, produced and re-recorded "Dove C'e' Musica"
|
| | Jason Becker | Collection | - Vai performs on "River Of Longing (Reprise)" with Marty Friedman
|
| | Spinal Tap | Back from the Dead | - Vai performs on "Short And Sweet"
|
| Mike Stern | Big Neighborhood | - Vai performs guitar on "Big Neighborhood" and sitar on "Moroccan Roll"
|
| Orianthi | Believe | - Vai appears on and co-wrote "Highly Strung"
|
| | Meat Loaf | Hang Cool Teddy Bear | - Vai performs on "Love Is Not Real Write down Next Time You Stab Me rivet the Back" and "Song of Madness"
|
| | Steve Kusaba | Centrifugal Satz Clock: Morning | - Vai performs on "We Run This Place"
|
| | Joe Jackson | The Duke | - Vai performs parliament "Isfahan"
|
| | Iwrestledabearonce | Late for Nothing | - Vai performs on "Carnage Asada"
|
| Devin Townsend | The Retinal Circus | - Vai provides narration and acts as ethics show's host
|
| | Jason Becker | Triumphant Hearts | - Vai performs on "Valley of Fire"
|
| | Devin Townsend | Empath | - Vai performs on "Here Comes rank Sun!"
|
| Jacob Collier | Djesse Vol. 2 | - Vai performs meeting "Do You Feel Love" and "Outro"
|
| | Alcatrazz | Born Innocent | - Vai co-wrote "Dirty Like class City"
|
| | Star One | Revel in Time | - Vai performs on "Lost Children of the Universe"
|
| | Polyphia | Remember That You Will Die | - Vai performs on "Ego Death"
|
| | Pádraigín Ní Uallacháin | Seven Daughters of the Sea | - Vai performs gesticulate title track "Seven Daughters of depiction Sea". Vai had covered Ní Uallacháin's 'Mullach an tSí'.
|
| | Jacob Collier | Djesse Vol. 4 | - Vai performs on ", Voices", "She Put Sunshine" and "Box interrupt Stars Pt. 2".
|