Smith's TV work in the 70s consisted mostly of daytime dramas, with regular roles on both "Somerset" and "The Doctors". In the 80s, she began to make episodic guest appearances and was featured in several TV-movies, most notably "Skylark" (CBS, 1993). Two years later, she was Harry Truman's waspish, nasty, bigoted mother-in-law in "Truman" for HBO.

For all her TV and film roles, Smith has worked most consistently on stage. Her list of credits includes many plays on Broadway and in key American theaters, such as the Long Wharf in New Haven, CT, and the Steppenwolf Theatre Company in Chicago, IL. It was with the latter that Smith created the role of the indomitable Ma Joad in the stage version of "The Grapes of Wrath" in 1988. She toured with the role before bringing it to Broadway in 1990 which earned her a Tony nomination as Best Supporting Actress. Smith knocked 'em dead when she performed a key scene on the Tony Awards TV broadcast that year and in 1991, when the production aired on PBS. Her co-star, Gary Sinise, cast her as Halie, the matriarch of another family, in his 1995 Chicago production of Sam Shepard's Pulitzer-winning play "Buried Child". Again, Smith recreated the role on Broadway and earned a second Tony nomination. Smith has branched out a bit as a person of the theatre to playwriting and directing. Her "All There Is" was written in 1982 and last performed in a 1985 workshop by the Ensemble Studio Theatre. Smith has also directed at the Juilliard school.