The 1960s saw her flourish in original roles in plays by some of the acknowledged masters of the American theater. Seldes originated the role of Blackie in Tennessee Williams' "The Milk Train Doesn't Stop Here Anymore" (1964) and had the title role of "Tiny Alice" (1965) in Edward Albee's play. In 1966, she achieved one of the pinnacles of her career as Julia, the much married daughter of a bitter couple, in Albee's blistering "A Delicate Balance," a performance that earned her a well-deserved Tony Award as Best Featured Actress in a Play. Five years, Seldes was elevated to the leading category for her strong turn in the one-night flop "Father's Day." (She lost to Maureen Stapleton.) By this time, she had a secondary career as a teacher at the drama division of The Juilliard School, a post she held from 1968 to 1990. The '70s saw Seldes establish her reputation for consistency. Between 1974 and 1976, she racked up more than 900 performances in "Equus," first as the magistrate and later as the mother of the troubled boy at the heart of the play. For her more than 1,000 performance run in "Deathtrap" (as the playwright's murdered wife), Seldes landed a spot in "The Guinness Book of World Records" and to honor her, the producers elevated her name to above the title. As the 80s dawned, she was cast in more patrician roles like the WASP mother in "Painting Churches" (1983-84), Woman B in Albee's Pulitzer-winning "Three Tall Women" (1992-96), the imperious mother to Teri Garr in the short-lived ABC sitcom "Good and Evil" (1991) and Aunt Brook in a 1992 episode of "Murphy Brown." She lent the same mixture of superiority and snobbery to such roles as the Widow Douglas in "Tom and Huck" (1995) and the neighbor who inadvertently passes a stolen computer chip to her pint-sized neighbor in "Home Alone 3" (1997). The actress displayed a warmer side as the town historian in "Affliction" and as Kevin Bacon's terminally ill mother in "Digging to China" (both 1998). While filming what she has termed her homage to Judith Anderson's Mrs. Danvers in "The Haunting" (1999), Seldes was tapped by former student Gerald Guitterez to replace the ailing Irene Worth in the 1999 Broadway revival of Jean Anouilh's "Ring Round the Moon." The pivotal role of the wheelchair-bound Madame Desmemortes allowed her to display her talents and Seldes earned a Best Actress Tony nomination for her efforts. Following the death of her second husband Garson Kanin in 1999, Seldes slowed but did not cease her theater and screen appearances, which included roles in Mike Newell's "Mona Lisa Smile" (2003) and George Clooney's period comedy "Leatherheads" (2008). She also appeared in the 2003 revival of the Broadway classic "Dinner At Eight." Marian Seldes died at home in Manhattan at the age of 86 on October 6, 2014.