“Fantastic, great!” sang Nancy Allen Lundy, performing an arietta from Leonard Bernstein’s opera “A Quiet Place.”

Similar sentiments prevailed offstage Saturday night at the Miller Theatre.

How could it be otherwise with the theater’s executive director, George Steel, conducting an all-Bernstein program? Included on the bill were “Serenade,” selections from “On the Town,” and “Kaddish 2.” The finale, the jazzy “Prelude, Fuge and Riffs,” put everyone in high spirits for a reception at Lerner Hall.

While sipping Champagne there after the show, guests praised the performers, such as violinist Jennifer Koh, soprano Amy Burton, and clarinetist Derek Bermel, who so kindly handed his bouquet to pianist Peggy DeAramond-Rogers.

Many singled out Mr. Steel.

“It was so full of music, it was wonderful, and George is wonderful,” said Bernstein’s daughter Jamie Bernstein Thomas.(His other children, Alexander and Nina, also attended).

Judith Lipsey, who underwrote the performance and is a member of the theatre’s board, called Mr. Steel “just a darling and a very good musician.” Ms. Lipsey added, in further admiration, “He went to Yale and he’s a Whiffenpoof.”

He’s also a father-to-be. His wife, Sarah Fels Steel, is due in March. They have just begun telling friends.

Those on hand to open Miller Theatre’s season included the music supervisor and orchestrator for “West Side Story,” Sid Ramin; pianist and composer John Musto (and Ms. Burton’s husband), who recently performed at the Moab Music Festival; members of the theater’s board of advisors, Mary Sharp Cronson, Stephanie French, and Olga Geroulanos-Votis; Brooklyn Philharmonic board member Cecille Wasserman; the director of Columbia’s National Arts Journalism Program, Andras Szanto; composer Chris Culpo; Craig Urquhart of the Leonard Bernstein Office; and actress Elaine Kussack.