After appearing in the American premiere of Jules Romain's Donogoo in 1961 at the Greenwich Mews Theatre, Isaac Babel's Sunset at the Chelsea Theater Center in 1966, and later that year as the star of David Starkweather's Ascent at The Playwrights Workshop, Porter was chosen as a member of original Obie Award-winning New York LaMaMa Troupe under director Tom O'Horgan ("Hair"), where she starred in the play and later film of "Futz!", and featured in Paul Foster's "Tom Paine" and "Melodrama Play" by Sam Shepard. A critic declared of her co-starring role in "Futz!": "Beth Porter makes the Whore of Babylon look like the Singing Nun."