A picture of a smiling Jennings, the sun in his face and blue skies behind him, was projected over the stage of the New York landmark.
The audience of about 2,000 people was filled with luminaries: Mike Wallace, Brian Williams, Dan Rather, Tom Wolfe, Larry King, Jon Stewart, Charles Gibson, Al Sharpton, Alan Alda, George Stephanopoulos, Bob Schieffer, Michael Eisner, Elizabeth Vargas and her husband Marc Cohn.
"An anchor is what keeps a ship from drifting into dangerous waters," said ABC News President David Westin. "It keeps us steady and secure during the night, and that's what Peter was to ABC News."
When they joined the network four decades ago, Ted Koppel recalled how he was known as the smart one and Jennings the handsome one. Jennings, who died of lung cancer Aug. 7, kept his looks to the end but was also "very, very smart," he said.
"From the time I first met Peter 41 years ago until our last meeting a few weeks ago, I felt a thrill whenever I saw him," the "Nightline" host said. "Not that many people have that charisma, that kind of animal magnetism that makes it difficult to focus on anybody else in the room."
Jennings, ABC's chief news anchor for more than 20 years, was also "famously attracted to women," Koppel said. "Even so, he only married four of them."
A handful of homeless people were also in the hall. Jennings' widow, Kayce, was startled recently when a homeless man approached to express sympathy for her loss; Jennings had befriended him during walks in Central Park.
Jennings frequently served meals to the homeless after leaving the ABC News studio and that night's broadcast of "World News Tonight," said Mary Brosnahan Sullivan of the Coalition for the Homeless.
"The Peter I knew was somebody of concrete action," she said.
Personal remembrances were interspersed with music: a gospel choir, violinist Natalie MacMaster, cellist Yo-Yo Ma, singer Alison Krauss and a jazz combo featuring Wynton Marsalis. Jennings was an insatiable jazz fan.
"For Peter, jazz was more than just a form of music, it was a way of looking at life," Westin said.
A hopeless sentimentalist, Jennings was "the only person I knew who got weepy telling about his service on jury duty," ABC producer Tom Nagorski said.
Alan Alda recalled Jennings as "complex and simple at the same time, knowledgeable and inquisitive, kind and tough at the same time, gracious and direct." He never left a social engagement without Jennings giving him a book; the last was a copy of the Constitution, he said.
Jennings never lost his Canadian identity, an honor guard from the Royal Canadian Mounted Police marched at the service, but was proud to also become a U.S. citizen a few years before he died.
Many of his ABC News colleagues have worn bracelets saying "what would Peter do?" since his death. For all the professional colleagues and anecdotes at the memorial, the pictures projected onstage showed an off-camera Jennings on family outings. Friends said his two children, Chris and Elizabeth, were his proudest accomplishments.
They were also the last to speak at the nearly two-hour remembrance.
"There is no way to express how much I miss my father," his son said. "Each day is, above all else, a day without him."