Dennis Dreith (born June 15, 1948) is a motion picture music composer, arranger, and conductor. He is also known as an influential advocate for studio musician's rights.
A native Californian born in Glendale, Dreith showed a talent for music at an early age. He learned to play a variety of keyboard and reed instruments while still in his teens. He formed a jazz combo in the late 1960s; the late music promoter Raymond D. Bowman (1917–2001) scheduled them for a number of Monday night concerts at the legendary Ice House in Pasadena.
Dreith grew to work as a musician in the film music industry and eventually worked with the Recording Musicians' Association (RMA), becoming its president, a post he held for over 15 years.
Although Dreith has been the composer for such films as Purple People Eater (1988), The Punisher (1989), and Gag (2006), he has never scored a major motion picture theatrical release. The Punisher was released in theaters worldwide except in the US (because of the studio's being bought by a company not interested in theatrical distribution). He is better known in the industry as an orchestrator and conductor of film music scores. His work (often uncredited) can be heard in the soundtracks of Jurassic Park, Misery, Braveheart, Addams Family, Sleepless in Seattle, Heart and Souls, A League of Their Own and others. He has been providing services to several well-known composers. Among them, John Williams, Lalo Schifrin, Dominick Frontiere, Marc Shaiman, Hans Zimmer, Elliot Goldenthal, Mark Isham and Cliff Eidelman.