In 1984 more than 1,000 of her costumes could be seen in five musicals running simultaneously on Broadway: “A Chorus Line,” “Dreamgirls,” “La Cage aux Folles,” “42nd Street” and “The Rink.”  She won three Tony Awards for costume design, for “Annie,” “Barnum” and “La Cage aux Folles.” Her many film credits included “Network,” “Semi-Tough,” “Moonstruck,” “Ghostbusters” and “Addams Family Values.”  “She made people look beautiful, which is a lot harder than you might think,” said the costume designer Martin Pakledinaz. “She also had the ability to see a production as a whole, the way one number grew out of the previous number and led into the one after that.”  Theoni Athanasiou Vachliotis was born on Aug. 22, 1922, in Salonika, Greece, and grew up in Athens. Her father was the surgeon general of the Greek Army and a member of the Greek Parliament. As a child she fixated on dolls and their clothes — throughout her life she maintained a large doll collection — and by the time she graduated from the American School in Athens in 1949, she had decided on theater as a career.  She enrolled at the Goodman School of Drama in Chicago and, stopping in New York on her way to Chicago, attended a showing of the 1946 film “Caesar and Cleopatra.” “A strange thing happened,” she told The New Yorker in 1973. “I was overwhelmed by the beauty of the flowing garments worn by Vivien Leigh.”  She added: “ ‘People can look so beautiful in clothes,’ I said to myself. ‘There is a mystery to costume.’ And that’s when it started.”  She made her debut as a costume designer in 1950, creating the clothes for “The Distaff Side,” a comedy by John van Druten produced at the Goodman Theater, and within a few years was teaching costume design at the theater’s school.  She also married Mr. Aldredge, an actor who was studying to become a director and who went on to make a successful career in New York. (He currently appears as Steve Buscemi’s father in the HBO series “Boardwalk Empire.”) He is her only immediate survivor.  After the couple moved to New York in 1959, Ms. Aldredge got off to a quick start when Geraldine Page, who had admired her work at the Goodman, persuaded Kazan to hire her for “Sweet Bird of Youth.”  “I made three outfits for Gerry — a negligee, a robe and a beaded navy blue evening dress with a lighter front because a bird’s stomach is always lighter than its back,” she told Architectural Digest in 1993. “So there you had Tennessee Williams writing, Geraldine Page and Paul Newman acting, and I thought, ‘Where do I go from here?’ ”  Onward and upward, it turned out. She won her first Tony nomination for “The Devil’s Advocate” in 1961 and became in constant demand on Broadway, designing costumes for “Cactus Flower”; the Edward Albee play “A Delicate Balance”; “Woman of the Year,” with Lauren Bacall; the revival of “Private Lives,” with Richard Burton and Elizabeth Taylor; “The Secret Garden”; “Nick & Nora”; and the 2006 revival of “A Chorus Line.”  She worked on more than 80 productions for Papp, including “The Threepenny Opera,” David Rabe’s “Sticks and Bones” and “Hair,” which all transferred to Broadway.  Papp once praised Ms. Aldredge for designing costumes that seemed to develop out of the characters onstage, and she herself insisted on the subservience of her craft. “You don’t take over a show,” she told The New York Times in 1984. “What you do is enhance it, because the costumes are there to serve a producer’s vision, a director’s viewpoint and, most importantly, an actor’s comfort. To me, good design is design you’re not aware of.”  In that regard “A Chorus Line” was a challenge, since nearly all the cast members wore slouchy rehearsal clothes until the spectacular closing number, which Ms. Aldredge envisioned as a visual feast of champagne-colored tuxedos and top hats. Bennett had wanted blazing red. No, she told him. Champagne was the color of celebration.  To generate ideas, she sat in on rehearsals, taking Polaroid pictures of each dancer. “I just borrowed from what they brought,” Ms. Aldredge said. “I took it as a compliment if people thought, ‘Well, they’re wearing their own clothes.’ ”  Ms. Aldredge designed for opera, ballet and television, as well as the theater, and in a curious detour in the 1980s she produced a ready-to-wear line for Jane Fonda called Jane Fonda Workouts.  For “The Great Gatsby” she generated hundreds of costumes in less than two weeks, a Herculean effort that might account for her irritation when the fashion press turned the spotlight on Ralph Lauren, who took credit for designing the clothes worn by Robert Redford and the film’s other male leads. Ms. Aldredge insisted that he had merely executed designs to her specifications.  Michael Gross, in his Lauren biography “Genuine Authentic,” wrote that Ms. Aldredge asked Paramount to take Mr. Lauren’s name off the film’s credits if he continued to bask in the limelight. His name stayed, in a secondary position, but Ms. Aldredge pointedly omitted his name when accepting her Oscar for the film.  The friction with Mr. Lauren was out of character for Ms. Aldredge, who had a history of working happily with even the most high-strung actors. She did know when to draw the line, however.  “Once an actress went overboard with notes to me about how she doesn’t wear pink,” she told The Chicago Sun-Times in 2006. “I told her, ‘Well, don’t wear it home then, sweetie. This is the theater.’ You kind of have to humor them. If you can’t love actors, you probably shouldn’t be a costume designer.”  A version of this article appears in print on January 22, 2011, on Page A19 of the New York edition with the headline: Theoni Aldredge, 88, Dies; Won Oscar for Costumes. Order Reprints| Today's Paper|Subscribe
Ms. Aldredge won an Academy Award for the costumes in “The Great Gatsby,” and created the clothing designs for hundreds of stage productions.