Muriel Balash began her career as an actress in the Borscht Circuit, alongside Elia Kazan and Shelley Winters, eventually establishing the Greenwich Mews Theater, which is remembered for pioneering cast integration. Through her New York theater connections, she began to direct Off-Broadway plays such as The Male Animal and This Property is Condemned. Under the mentorship of Sidney Meyers and Merrill Brockway, Balash transitioned to a successful editing career on such programs as Camera Three and Great Performances. Wanting to have creative control over her work, Balash began directing documentaries including Gertrude Stein, Gertrude Stein, Gertrude Stein (1982), Jean Louis Barrault - A Man of the Theatre (1984) and Pepito’s Dream (1992). 

Balash was elected to the DGA Eastern Directors Council in 1982, serving as an alternate for five terms and as a Council member for four terms. She also served as an alternate on the National Board from 1987-1989.