Brett Leonard (born May 14, 1959) is an American film director, producer, and music video director specialising in the science fiction and horror genres. A few of his films, such as The Lawnmower Man (1992) and Virtuosity (1995), feature groundbreaking computer animation and visual effects.

Leonard's work with the IMAX 3D process set him apart from most directors, having gained early experience with this cutting-edge presentation medium directing T-Rex: Back to the Cretaceous in IMAX 3D. The film became the first number-one hit 3D movie to gross over $100 million worldwide (on IMAX screens alone).

He created a sensation when he took his Swarm Cam-Fusion Station onto The Tonight Show with Jay Leno and, with guest Billy Idol, implemented one of the first live webcasts ever from the House of Blues in Los Angeles.

Creative Artists Agency and Intel Corporation hired him to direct a state-of-the-art "interactive show" for CAA/Intel Media Lab to introduce the Hollywood community to the "future of entertainment," digitising actor Danny DeVito and using live performance animation to create the interactive animated character "Mr. Head," who guided the audience/participants through the experience.

In the music video genre, Brett directed Peter Gabriel's "Kiss That Frog," the first all-computer graphic (CGI) music video/motion simulator ride film to tour the world, becoming the wildly popular themed entertainment attraction to win him a 1994 MTV Music Video Award.

In 2009, Brett directed the documentary Hole in the Head: A Life Revealed. This feature-length documentary tells the story of Vertus Hardiman and nine other young children, attending the same elementary school in Lyles Station, Indiana, who, in 1927, were severely irradiated during a medical experiment conducted at the local county hospital. The experiment was misrepresented as a newly developed cure for the scalp fungus known as ringworm. In reality the ringworm fungus was merely the lure used to gain access to innocent children whose unsuspecting parents blindly signed permission slips for the treatment. Vertus was five years old and the youngest; after 20 years of friendship with writer/producer Wilbert Smith through their church choir, Vertus tells Wilbert his story, exposing the severe physical complications caused by the experiments. This crime had severe physical complications for Vertus—namely a harshly irradiated and malformed head, with an actual hole in his skull.

In 2012, Brett formed a new concept in musical cinema called PopFictionLife. Seeing the proliferation of small high-definition screens on smartphones, tablets, and laptops, PopfictionLife "FragFilms" are full-length feature movies with existing artists that have multiple free "Frags" (fragments) of the movie that are watchable, shareable, and embeddable in social media, blogs, and webpages. Brett's latest film is a PopFictionLife FragFilm called The Other Country—Starring Burlap to Cashmere. The film also stars Samantha Lockwood and America's Next Top Model winner Nicole Fox.

In 2017, he called for a use of the term "virtual experience" instead of "virtual reality."Brett Leonard, licensed under CC-BY-SA, full list of contributors on Wikipedia.