The Kennedy Center 2011 Spring Gala Performance. Front row: Michael Cook, Elisabeth Holowchuk, Christoph Eschenbach, Michael Kaiser, and host Smokey Robinson. (Margot Schulman/ Kennedy Center)

When David Rubenstein was named chairman of the Kennedy Center last year, the board gave him one mission: Persuade president Michael Kaiser to stay.

Kaiser, 57, had planned to leave after a decade, but Rubenstein (and Kaiser’s annual $1.1 million salary) prevailed. So Sunday’s gala, originally planned as a retirement party, turned into a celebration of his 10 years as the head of the national arts center.

Some critics (including at this newspaper) charge that the center has been playing it too safe artistically, but that’s clearly not the view of the board or donors who credit Kaiser for bringing world-class performers to D.C. and transforming the center into one of the world’s leading arts institutions — and profitable, to boot. “We are the new Carnegie Hall,” said Rubenstein, who just gave another $10 million to the Kennedy Center.

Will Todd and Mary Mitchell Purvis pose at the Kennedy Center after Purvis said “I do.” (Daniel Schwartz)

The black-tie dinner and show, emceed by Smokey Robinson, included performances by Renee Fleming, Barbara Cook, Brian Stokes Mitchell and others; in video tributes, Prince Charles praised Kaiser’s “remarkable genius for sorting things out.” A team of powerhouse donors (Adrienne Arsht, Betsy DeVos, Alma Gildenhorn, Helen Henderson, Ann Jordan, Alma Powell, Catherine B. Reynolds, and Vicki Sant) raised $2.8 million for the night; the crowd of 1,000 was peppered with billionaires, senators, Supreme Court justices and other bigwigs.

Kaiser emerged on stage at the end of the show, thanking donors, co-chairs, staff and two special people: His parents, Harold and Marion Kaiser. “When I was four years old, my parents took me to see ‘The Music Man’ starring the ever-young Barbara Cook,” he said, glancing downstage to the 83-year-old singer. “The magic of the theater took hold of me that night and it’s never let go. Thanks mom and dad, thank you Barbara.”

The man of the hour was still taking it all in at the post-performance party on the rooftop. “It was surreal because I’m not used to having things be about me,” he told us. “I’m used to being backstage.”

He wasn’t the only one having a big night: Will Todd, a legislative assistant to Sen. Thad Cochran, proposed to girlfriend Mary Mitchell Purvis.

Todd, 28, arranged for a Kennedy Center staffer to pull him from the show, claiming the senator needed his help. A few minutes later, they escorted Purvis, 24, to the center’s rooftop, where Todd was waiting with a ring. “It was burning a hole in my pocket all night,” he said. She said yes, and their families and Cochran joined them for a champagne toast. “We love the Kennedy Center and we love the arts, so that’s been a special place for us,” he told us.