Sarmiento made her directorial debut with the documentary "Un sueño como de colores" (1972) about a group of Chilean women dedicated to striptease. Her later work as a director, usually in melodrama, romantic drama and costume drama, has also often featured strong female characters who face machismo and sexism. Her debut feature "Notre mariage" (1984) was a Grand Prix winner for Best New Director at the San Sebastián International Film Festival, her 1991 film "Amelia Lópes O'Neill" was entered into the 41st Berlin International Film Festival and her Napoleonic war epic "Lines of Wellington" competed for the Golden Lion at the 69th Venice International Film Festival.