“I did that already” were the words on a ring Beverly Sills’s husband gave to her, a sentiment meant to pay tribute to the opera star who became the art form’s greatest populist, a visionary arts administrator, a powerful fund-raiser, a devoted wife, and the mother of two children.

But there was one task she could not do for herself: gather a group of luminary artists, politicians, and administrators to offer thanks for her life and to show how her spirit lives on after her death from lung cancer at age 78 on July 2.

Almost all of the 3,800 seats of the Metropolitan Opera House were occupied for the two-hour program yesterday, which included performances by conductor and pianist James Levine, tenor Placido Domingo, and fellow sopranos Anna Netrebko and Natalie Dessay. Earlier in the day, it took only half an hour for 2,000 free tickets to the memorial to be distributed.

“She lit up this stage and many others, and she lit up this city,” Mayor Bloomberg said, noting that she was born and educated at public schools in Brooklyn. “She was Queen of the Night, Queen of the Nile, and Queen of New York. God bless you, may your rest in peace,” he said, playing on her roles in productions of Mozart’s “The Magic Flute” and Handel’s “Giulio Cesare.”

The New York City Opera, where she made her debut in 1955, was her first home at Lincoln Center for the Performing Arts. Later, as chairwoman of what is the city’s leading arts complex, she began its redevelopment, a project that will be completed in a couple of years.

The City Opera’s chairwoman, Susan Baker, spoke for many people at Lincoln Center, including guards and ticket-takers, when she said, “You’ll be at our side whenever we can combine vigorous intellect with a sense of abiding hope and optimism.”

The general manager of the Metropolitan Opera, Peter Gelb, whom Sills hired, said that Sills would often call him after he’d started the job and ask, ironically, “Peter, is everything perfect?”

“Sadly, Beverly, without you the world of opera is less perfect,” Mr. Gelb said.

The most poignant themes were her cheerfulness in the face of personal difficulties and her devotion to her daughter Meredith “Muffy” Greenough, who was born deaf and has multiple sclerosis.

“We were best friends who laughed together every day,” Ms. Greenough said in remarks read by Barbara Walters.

“‘Bubbles’ was the perfect name for her,” Carol Burnett said, recalling how, during a visit to California, the soprano asked to be picked up at the “Beverly Sills Hotel.”

Her brother Stanley Sills described the grand entrance she made at birth, which took place in their home; she weighed 10 pounds and measured 23 inches.

She continued to make grand entrances until her final moments. Visiting during her last stay in the hospital, Henry Kissinger found her with her eyes closed and attached to tubes. A nurse mistook the former Secretary of State for newscaster Walter Cronkite. Sills opened her eyes and said, “Walter Cronkite is older and doesn’t have an accent,” Mr. Kissinger recalled.

Many of the speakers noted Sills’s prowess as a fund-raiser, not only for the two opera companies at Lincoln Center and for the complex itself, but also for the March of Dimes and the National Multiple Sclerosis Society.

While serving as chairman of the performing arts complex, Sills sent a letter to a donor, Nathan Leventhal, himself a former president of Lincoln Center: “I want to thank you for your gift. I can’t tell you what a gorgeous pair of earrings I bought with your contribution. Keep those unrestricted gifts coming.”

A onstage screen showed photographs from Sill’s career and two videos: One of Sills performing a comedy/musical routine, “Only an Octave Apart,” in which the soprano outshines the “bass,” sung by Ms. Burnett, and one of Sills at age 8 in the film “Uncle Sol Solves It,” performing “Il Bacio” by Luigi Arditi. It may have been the most casual fashion moment of her career: She wore a sailor’s suit and a Shirley Temple head of curls.

Wearing the ring, a gift from Sills, the television correspondent Barbara Walters said, “No one was more glorious and talented in every way. You did that already. So rest now, my darling friend.”