Medium 

The DVD releases of The Fourth Season, The Fifth Season, The Sixth Season and The Seventh Season did not include any episode-length audio commentaries.

Special thanks to John F. for helping compile this information.

 

Listing 12 commentaries.

Medium - The Complete First Season cover

Medium - The Complete First Season
4 commentaries
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Episode 1.06: “Coming Soon”
Commentators: Glenn Gordon Caron Moira Kirland

Episode 1.11: “I Married a Mind Reader”
Commentators: Ken Kelsch Jessica Kender

Episode 1.13: “Being Mrs. O'Leary's Cow”
Commentators: Chad Lowe Ronald L. Schwary

Episode 1.14: “In the Rough”
Commentators: Glenn Gordon Caron Rene Echevarria

Medium - The Complete Second Season cover

Medium - The Complete Second Season
5 commentaries
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Episode 2.03: “Time Out of Mind”
Commentators: Glenn Gordon Caron Jessica Kender Robert Doherty

Episode 2.08: “Too Close to Call”
Commentators: Rene Echevarria Miguel Sandoval

Episode 2.09: “Still Life 3-D”
Commentators: Glenn Gordon Caron Ronald L. Schwary

Episode 2.10: “The Reckoning”
Commentators: Moira Kirland Aaron Lipstadt

Episode 2.12: “Doctor's Orders”
Commentators: Rene Echevarria Mark A. Sheppard

Medium - The Third Season cover

Medium - The Third Season
3 commentaries
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Episode 3.01: “Four Dreams, Part I”
Commentators: Glenn Gordon Caron Larry Teng

Episode 3.02: “Four Dreams, Part II”
Commentators: Aaron Lipstadt Javier Grillo-Marxuach

Episode 3.16: “Whatever Possessed You”
Commentators: Miguel Sandoval Jessica Kender

Involving 13 commentators.