| Title | Year | Album | Lyricist | Length | Notes |
|---|
| " Entr'acte" | | The Astonishing | Instrumental | |
| "" | | Awake | Kevin Moore | |
| "A Better Life" | | The Astonishing | John Petrucci | |
| "A Change of Seasons" | | A Change of Seasons | Mike Portnoy | | Originally written in and supposed to appear on Images and Words, but cut due to the album already being too long.Dream theater 40th anniversary tour Dream theater 40th anniversary tourDream theater tour 2024Dream theater setlist 2024 europeDream theater setlist predictionsSetlist dream theater 2024The song was re-worked and released on the EP A Change of Seasons. The original version was never officially released. |
| "A Crack in the Mirror" | | — | Instrumental | | Extended intro added to "The Mirror".
Only played live during the Waking Up the World Tour (–95) and never officially released. |
| "A Fortune in Lies" | | When Dream and Day Unite | John Petrucci | |
| "A Life Left Behind" | | The Astonishing | John Petrucci | |
| "A Mind Beside Itself: I.
Erotomania" | | Awake | Instrumental | |
| "A Mind Beside Itself: II. Voices" | | Awake | John Petrucci | |
"
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