But on March 11, 1973, Kurt Peterson, along with Craig Zadan and Neil Appelbaum organized the Sondheim: A Musical Tribute concert at the Shubert Theatre, where Sondheim's latest show, A Little Night Music, was previewing.
The concert brought together 30 or so stars of his shows--including Angela Lansbury, Larry Kert, Chita Rivera, Len Cariou and others. And it crystallized for Broadway that Sondheim's body of work was not just impressive, but extraordinary.
Highlights of the concert were later released on record, complete with the show's distinctive Scrabble-tile logo.
Here is a mini documentary on the concert.