Reitman began his career as a stage and TV producer and turned out his first feature film in 1971. Among his initial low-budget Canadian productions were two striking early horror films directed by David Cronenberg, "They Came from Within" (1975) and "Rabid" (1977). As a producer and/or director, Reitman played a significant role in the film careers of several Second City (Chicago and Toronto-based) performers who first gained fame on "Saturday Night Live"--Bill Murray, Dan Aykroyd, and John Belushi. Aykroyd was featured in "Greed", a Reitman-produced variety show for Canadian TV. Murray made a big splash on screen in the Reitman-directed "Meatballs" (1979) and "Stripes" (1981). Both actors also appeared in his blockbuster comedy "Ghostbusters" (1984), Reitman's biggest commercial success to date. John Belushi's all-too-brief movie stardom, meanwhile, was initiated by his riotous performance in the Reitman-produced "National Lampoon's Animal House" (John Landis, 1978).

"Animal House" marked the beginning of a fruitful collaboration between Reitman and Harold Ramis, who scripted that frat war comedy. Ramis also worked on the films "Stripes" (as screenwriter and actor), "Ghostbusters" (as screenwriter and actor) and "Ghostbusters II" (as screenwriter and actor). Reitman also tried to soften the image of Arnold Schwarzenegger by directing him in the comedy "Twins" (1988), teaming him with the diminuitive Danny DeVito, and by producing "Kindergarten Cop" (1990). Similarly but considerably less successfully, Reitman produced "Stop! or My Mom Will Shoot" (Roger Spottiswoode, 1992) for Sylvester Stallone.

Until John Hughes' "Home Alone" (1990) supplanted it, Reitman's outsized supernatural spoof was the highest grossing comedy in movie history. The quirky "Ghostbusters" mythos quickly became part of 80s popular culture, yielding a hit single, tons of merchandise, a long-running cartoon series (on which he served as executive consultant), "The Real Ghostbusters" (1986-88) which evolved into "Slimer! and the Real Ghostbusters" (1988-91), and the inevitable sequel, "Ghostbusters II" (1989, directed by Reitman).

Reitman scored a surprise hit as the executive producer of "Beethoven" (Brian Levant, 1992), a canine comedy starring the deadpan Charles Grodin. He returned to directing after a three-year hiatus with "Dave" (1993), a political satire starring the talented cast of Kevin Kline, Sigourney Weaver, Frank Langella, Ben Kingsley, and Grodin. As a modern variation on Twain's "The Prince and the Pauper", it suggested Akira Kurosawa's "Kagemusha" (1980) as directed by Frank Capra. The director fared less well with his follow-up comedies. "Junior" (1994) reteamed Schwarzenegger and DeVito in an improbable story of a male scientist (Schwarzenegger) who becomes pregnant while "Father's Day" (1997) teamed Robin Williams and Billy Crystal in an Americanized version of a French farce about two men searching for a runaway teen they both think they fathered. He next teamed Harrison Ford and Anne Heche for the romantic comedy, "Six Days, Seven Nights" (1998).

Reitman's other credits as a director include "Cannibal Girls" (1972) and "Legal Eagles" (1986), with Debra Winger and Robert Redford, while his producing credits include the animated "Heavy Metal" (1981) and the Howard Stern biopic "Private Parts" (1997).