“‘Treasures’ is a very subjective word,” the curator of the Billy Rose Theatre Division of the New York Public Library, Robert Taylor, said.

But even the harshest of critics would be hard-pressed not to find a treasure within the trove of the “Stars and Treasures” exhibit, which opens tomorrow at the NYPL, where over 300 items and clips from 30 different theater productions are available for viewing.

Upon entry to the exhibit, which is arranged in six thematic sections and features a “mini-theater” for viewing video clips, patrons are greeted by a bevy of medals of statuettes, including Burl Ives’s Academy Award for his performance in “The Big Country,” critical awards including an Emmy and a Drama Desk, and, of course, the crème de la crème of theatrical accolades, a Tony.

But while the first stages of the showcase celebrate performances, the rest of it heralds more behind-thescenes elements. Not a keepsake is overlooked; among those on display are an Isamu Noguchi-sculpted bust of actress Aline Macmahon, letters from Woody Allen during the onset of his career, and show posters drawn by legendary New Yorker cartoonist Al Hirschfeld.

Paying homage to the discipline’s provenance is the Early British Theatre section, which features letters from noted actor Charles Kean, an obituary of Sir Henry Irving, who was the first actor ever to be knighted, and an announcement and ticket for the first Shakespeare Jubilee festival, which was organized by luminary David Garrick in 1769.

Achievements from other parts of the globe are highlighted in the International Theatre area, where memorabilia of Japanese Edo theater and a poster from the first Israeli production of “West Side Story” are on view.

Theatre in America spotlights items from this side of the pond; a locket containing actor Edwin Booth’s portrait and lock of hair sits near a letter he wrote about voting for Abraham Lincoln. There is also a program from the performance at Ford Theater where Mr. Lincoln would encounter another member of the Booth family: John Wilkes Booth, presidential assassinator and brother of Edwin.

A poster from a P.T. Barnum show is featured in the Theatre of Spectacle section, while the Theatre of Illusion features handwritten letters from an embittered Harry Houndini, who laments the proliferation of “rotten imitators.”

“Some of these things are irreplaceable,” Mr. Taylor said. “I don’t think it could even be valued.”

The notion of treasure may be subjective, but for the staff of the Billy Rose Division, the idea of a star is a democratic one. After compiling a list of living Tony Award winners, the staff voted on the 50 whose legacy they predicted would last past closing curtains. (James Earl Jones won top billing with the number-one spot.)

The “stars” were then contacted and asked to donate items, which resulted in the acquisition of Harvey Fierstein’s dressing room mirror, a script from the 1994 revival of “Carousel” that was annotated in Audra McDonald’s hand, and Angela Lansbury’s Halston-designed kimono from the revival of “Gypsy.”

Also contributing to the exhibit was Joel Grey, who won a Tony for his supporting role in “Cabaret,” and who also appeared in person at a preview of the collection. “My life’s work and my destiny is still in the theatre,” Mr. Grey said. He contributed a trunk designed by Fred Ebb, one half of the wonder-duo that begat “Chicago” and “Cabaret.” During “Me and My Shadow,” a piece in Mr. Grey’s one-man road show, actor Charles Repole would enter the trunk and provide the illusion that the case was dancing in step with Mr. Grey.

Whether it’s a throwback to a bygone era or a tribute to the legacy that lives on, the exhibit maintains memories in danger of vanishing with their proprietors’ final bows. As the director and chief executive officer of the research libraries at the NYPL, David Ferriero, said, “The division preserves the moments of the theater that would otherwise disappear when the stage lights are lowered.”