(written from a Production point of view)
Prior to his work on Star Trek: The Next Generation, Mann worked as set designer on the music drama Coal Miner's Daughter (1980, set decoration by John M. Dwyer), the fantasy film Xanadu (1980), the television drama Leave 'em Laughing (1981, with assistant property master Alan Sims), the comedy The Man Who Wasn't There (1983, with production illustrator Joseph Musso), the comedy Meatballs Part II (1984), the comedy Fletch (1985), the romance Pretty in Pink (1986), the comedy Ferris Bueller's Day Off (1986, with Alan Ruck), the comedy Planes, Trains & Automobiles (1987), and the romance She's Having a Baby (1988).
Further credits as set designer include the action film Tango & Cash (1989, with Teri Hatcher), the science fiction sequel Predator 2 (1990, starring Kevin Peter Hall), the comedy Almost an Angel (1990), the comedy True Identity (1991), the thriller Jennifer Eight (1992), the action drama Speed (1994), the drama Life as a House (2001, with Scott Bakula), and the pilot episode of The Lyon's Den (2003).
Mann also worked as assistant art director on the comedy The Great Outdoors (1988), the drama Dead Poets Society (1989, with art direction by Sandy Veneziano), and the comedy Uncle Buck (1989). His credits as art director include the action film Hard to Kill (1990), the comedy sequel Sister Act II: Back in the Habit (1993, starring Whoopi Goldberg), the drama There Goes My Baby (1994), the television movie 44 Minutes: The North Hollywood Shoot-Out (2003), the television series Summerland Beach (2004-2005), and the comedy sequel Garfield: A Tail of Two Kitties (2006). In addition, Mann worked as production designer on the drama series Chicago Hope between 1994 and 2000.