Master Class was a resounding commercial success. It ran from November 1995 to June 1997 on Broadway, recording over six hundred performances. By 1997, there also had been about forty productions abroad, including those in Argentina, Estonia, Germany, Israel, Italy, Hungary, Japan, Korea, New Zealand, and Turkey.

Zoe Caldwell received high praise for her performance as Callas, whom she played from opening night until June 28, 1996, and for which she won a Tony Award. Brad Leithauser, in Time, wrote that ‘‘you don’t doubt that if [Caldwell] could only transfer what’s inside her to her pupils, they would sing like angels.’’ However, Caldwell’s strong performance tended to obscure, according to Leithauser, the shortcomings of the play. He questioned the division of the play into two acts, since ‘‘the second act doesn’t deepen, it merely extends.’’ He also declared that McNally’s attempt to ‘‘drive [the play] toward an old-fashioned theatrical climax (one of the students ultimately mutinies against Callas’ bullying) feels contrived.’’ These alleged shortcomings, however, did not stop the play from winning the number six slot in Time’s end of year list of the best plays of 1995.

Nancy Franklin in the New Yorker also remarked on Caldwell’s outstanding performance (‘‘Caldwell plays Callas with . . . steely force and conviction’’) but felt that the play did not serve the historical Callas well. She argued that the recordings available of Callas’s Master Classes make it clear that ‘‘as a teacher Callas was a consummate professional . . . . she was unfailingly attentive to her students, and didn’t use the audience as a foil for her egomania,’’ unlike the Callas in the play. Franklin’s conclusion was that because of McNally’s desire to present Callas as an ‘‘artistic personality’’— complete with haughty, sardonic manner— and to discover what it was in Callas that so moved her audiences, the play ‘‘says more about its author than about its subject . . . . Master Class doesn’t get us any closer to Callas.’’

When Patti Lupone took over from Caldwell on Broadway in the summer of 1996, Vincent Canby, reviewing the production for the New York Times, commented that the play was more ‘‘complex and difficult than it first seemed.’’ He was referring to the way Master Class goes back and forth between Callas’s memories and her interactions with her students. Canby described the Callas of the play as ‘‘a spectacular pousse-café of gallantry, [b—— ]iness, dedication and impatience with the secondrate.’’ Lupone, who played the original title role in the musical Evita, did not quite convince Canby with her performance, which he described as possessing ‘‘more power than control’’:

Under Leonard Foglia’s direction, she makes all the right moves, but she doesn’t execute them with the innate grace of the woman who was possibly the twentieth century’s most dazzling opera star. There’s something slightly crude about this Callas when she should be cleanly, imperially demanding.

Later actresses who have taken on the role of Callas include Faye Dunaway, who plays Callas in the film version of the play. Dunaway appeared in a touring production of Master Class at the Shubert Performing Arts Center in New Haven, Connecticut, in 1997. Alvin Klein, reviewing the production for the New York Times, found some weak spots in her interpretation of the role and argued that she did not own it as completely as Caldwell and Lupone had. He pointed in particular to her veiling of her emotions in the crucial section when the tenor moves Callas deeply with his rendition of an aria from Puccini’s Tosca: ‘‘Ms. Dunaway’s reaction to his splendid performance is guarded. She masks her tears, turning away from the audience, after he leaves.’’ Although Klein acknowledged that there may be some merits to the choice Dunaway made, he adds, ‘‘yet Ms. Dunaway’s reserve narrows the performance and works against much of the role as Mr. McNally crafted it.’’ Since Klein regarded the play as ‘‘little more than a sketch for an actress of largesse to fill in with heartbreak and transcendence,’’ he claimed that a less than perfect performance in the leading role merely exposed the relative weakness of the script.