Rainer began integrating slides and short films into her dance work as early as 1968, and made her feature debut with "Lives of Performers" (1972), an outgrowth of her dance background. A politically committed artist, her film work evolved away from the influences of the so-called American avant-garde (materialist, structuralist films) to concern itself not only with the film medium, but with its modes of representation (of gender, race, class, etc.). Rainer's films break with the illusionism of Hollywood, disrupting the story, relying heavily on verbal language, and dealing most often with power relations (particularly between the sexes). Her use of Brechtian distancing effects (e.g. extended voice-overs, combining documentary with enacted footage) is comparable to the work of Jean-Luc Godard.
Collage-like, multi-layered and theoretically-aware, Rainer's "The Man Who Envied Women" (1985), is perhaps her most ambitious film, dealing with psychoanalytic and narrative theory, aging, US policy in Central America and New York's housing crisis, while quoting substantially from such major thinkers as Michel Foucault, Frederic Jameson and Julia Kristeva. Her "Privilege" (1990) focused on a group of women facing menopause while "Fast Trip, Long Drop" (1993) profiled the HIV-positive activist and filmmaker Gregg Bordowitz as he dealt with his homosexual and Jewish identities and the political dimension of the AIDS crisis. In 1996, Rainer directed "MURDER and Murder", a meditation on the sexual politics of a late in life affair between two women.