Mr. Friedman (center) with Mad. Sq. Art's Debbie Landau and David Berliner. Photo by Ben Gabbe/BFAnyc.com (Courtesy Fitz & Co.)

Last week's Mad. Sq. Art benefit honoring Martin Friedman, a long-time director at the Walker Art Center and consultant on the public art projects in Madison Square Park, attracted about 300 guests, with more than a few art icons—John Baldessari, Chuck Close, Christo, David Hockney, Frank Stella and Mark di Suvero among them. Philip Glass performed Metamorphosis No. 2. Mr. Baldessari was...really tall.

Most impressive, though, was the $1 million in proceeds raised for the newly established Martin Friedman Fund, which will create permanent support for Mad. Sq. Art as well as help set up the Martin Friedman Curator position.

Madison Square Park has been the site of public installations by artists like Jessica Stockholder, William Wegman, Sol LeWitt, Mr. di Suvero and, most recently, Charles Long, whose "Pet Sounds" show will be on view in the park through Sept. 2.

“I will treasure forever being described as a bonehead,” said Martin Friedman, who is in his late 80s, and who served as director of the Walker Art Center in Minneapolis for 26 years before retiring in 1989 and, eventually, becoming an advisor to the park. He was sitting in his art-filled apartment (Claes Oldenburg sketches and sculptures, Sol LeWitt wall drawings) on the 12th floor of a building in Greenwich Village last week, reminiscing about the incident that earned him his epithet. When the park displayed life-size sculptures of naked, standing men by Antony Gormley on rooftops two years ago, The New York Post fretted about their being mistaken for potential suicides in an article bearing the headline “Jump Dummy Jump,” that referred to the exhibition’s “boneheaded organizers.”

In a career devoted to helping artists realize improbable projects, and in so doing creating a cultural mecca in an improbable part of the country, being called a bonehead is easy enough to laugh off. In 1971, less than a decade into his tenure at the Walker, Mr. Friedman overhauled its campus, putting up a new, column-free, warehouse-like building built to suit the way artists were working on challenging, large-scale pieces—at what he still boasts was the low, low cost of around $4.5 million, which, even adjusted for inflation, is still modest compared to today’s museum buildings, which clock in in the hundreds of millions of dollars. And he created a sculpture park—he’s always, he said, “had a particular thing for sculpture,” and when he started at the Walker the public knew more about painters, “hero figures” like Jackson Pollock. He turned the Walker into a museum that focused on the art of its time, and built a world-class collection.

“Should I tell you how much they paid for it? Martin hates it when I do that,” Chuck Close said to The Observer mischievously over the phone. In 1969, Mr. Friedman made the Walker the first museum to buy one of Mr. Close’s paintings, Big Self-Portrait (1968). He paid $1,300. As for that warehouse-like building, “he learned that from our studios,” Mr. Close said. Mr. Friedman would make regular visits to New York in the ’60s and ’70s. “None of us had any money. He would say, ‘Let’s go to Chinatown and have Chinese food,’ and then we would just collect every artist we saw while we were walking. We’d start out with two or three and by the time we got there we would have 20, and he’d happily pick up the check.” He bought them dinner and they gave him tips on which artists to visit, whose work to buy, who to bring to the museum—artists like Richard Serra and Keith Sonnier.

“He wanted to know what was going on and what we thought,” said Mr. Close. “It’s not often that you get a museum director who will follow you almost anywhere you want to go. Now that role would be maybe described as an art consultant or something. Now there are people who are paid to take people around, and see the art you are supposed to see.”

He wasn’t keen just on visual art. The Whitney may be lauded for giving dance pride of place in this year’s Biennial, but that sort of thing was old hat for the Walker by the late ’70s. Mr. Friedman brought in Merce Cunningham, John Cage, Meredith Monk and Twyla Tharp and gave them residencies. “With Philip Glass, in the beginning, we were lucky if we could get one row”: he’d seat his two small children “and people from the neighborhood.” He started a department and hired curators for performance at a time most museums treated it as an ancillary activity, or part of the education department. “I got him to bring Ray Johnson out to give a lecture,” said Mr. Close. “Ray never did anything the way someone expected him to do it. He called it ‘A Thoreau Away Lecture,’ and he threw the lecture all over the audience. He streaked his own lecture, naked.”

Mr. Friedman booked acts like “The Once Group”—“they were like a traveling circus”—sight unseen. “I don’t think many museums would do that. I still don’t know why I did it.” The Walker, he concluded, philosophically, “was a playpen.”

A serious one. He gave a talk recently "where he was asked him what his role was at the Walker, and he said, ‘To a large extent to be a nuisance,’” said Hirshhorn Museum and Sculpture Garden director Richard Koshalek, one of a number of museum professionals Mr. Friedman mentored over the years—they include Graham Beal, now director of the Detroit Institute of Arts; Jan Van Der Marck, the first director of Museum of Contemporary Art, Chicago; and Nigel Redden, director of the Lincoln Center Festival. “He also said, ‘I like to see people change their minds.’”

Which is maybe why he helped Christo and Jean-Claude in their 18-year quest to wrap the Reichstag in fabric. (They did, in 1995.) Headway was made during the Carter administration, Christo told The Observer, thanks to Mr. Friedman, who was close to Walter Mondale’s wife.

At a time when museums are increasingly beholden to celebrity, to money, to crowd-pleasing shows that amp up attendance—with directors as businessmen, or Barnum-style showmen—Mr. Friedman’s leadership, with its emphasis on research and dialogue with artists should, Mr. Koshalek says, be a model. (Sometimes he served as a model, cast in plaster for George Segal several times. He’s waiting in a breadline in the 1997 FDR Memorial; it looks a little like something out of Dante.) “Art can sometimes be entertaining,” Mr. Koshalek remembers Mr. Friedman saying, “but entertainment is never art.”

Whitney Museum director Adam Weinberg, a former photographer, spent the ’80s at the Walker, first in education and then as a photography curator. “What hit me when I got there was that I could be a lover of objects but also a lover of artists’ processes.”

Mr. Friedman was the first person Mr. Weinberg met who passed F. Scott Fitzgerald’s test for a first-rate intelligence: the ability to hold two opposing ideas in mind at the same time. “And that’s what artists do in many ways,” Mr. Weinberg said. He was also a marathon worker. “Everybody was exhausted. It was like working in a law firm or Wall Street. At 10 at night he’d be laughing, he’d say, ‘Isn’t this fun?’ He’s 60 years old, and I’m 35, and he’s thinking it’s fun.”

In 1988, the year before he retired, he installed on the Walker’s grounds a 30-foot-tall, 50-foot-long spoon with a cherry at its tip, by Claes Oldenburg and Coosje von Bruggen. Its image is on posters in Minneapolis’s airport. If Minneapolis is the Paris of the Midwest, the Walker is its Louvre, D’Orsay and Eiffel Tower.

Mr. Friedman and his wife, Mickey, a design and architecture curator who championed Frank Gehry, moved to New York, but he became restless; retirement didn’t suit him. He consulted for the Nelson Atkins Museum in Kansas City, Mo., developing the Kansas City Sculpture Park. “I became the yard man,” he said. In 1994 he brought in monumental badminton birdies by Mr. Oldenburg and von Bruggen . (In 2009 he was thanked with a gift funded by the Hall Family Foundation: he got to commission anything and chose a 56-foot-high stainless steel sculpture of a tree by Roxy Paine.)

Meanwhile, his services as a yard man were needed in New York. In 2004, he got a call from Debbie Landau, now president of the Madison Square Park Conservancy, who was developing the park with Danny Meyer, who would famously open his first Shake Shack there. She wanted an art program and started with a couple of shows put on by the Public Art Fund. In 2003, she helped establish the Conservancy, and a series of meetings brought her to Mr. Weinberg, who suggested she contact Mr. Friedman, whom he called the father of the modern sculpture garden.

“Adam said, ‘Martin doesn’t have much to do. He’ll come cheap, for free,’” Mr. Friedman said, laughing. “So I did. And I was delighted because I felt like I’d been taken off the shelf, dusted off and given the chance to work with some talented people.”

At the time, the park had just installed a set of huge, angular steel sculptures by his old friend Mark di Suvero, one of whose giant pieces he’d installed at the Walker in the early ’70s. Shortly after retiring, Mr. Friedman had helped Mr. di Suvero with Socrates Sculpture Park, the outdoor art venue Mr. di Suvero, along with a group of artists and community members, had founded in an abandoned landfill in Long Island City in 1986. “We were endangered by—let’s call them entrepreneurs of real estate—who wanted to take this place we had cleaned up,” Mr. di Suvero recalled. “He came in and he taught us how to build a board of trustees.”

The di Suvero show was getting Ms. Landau publicity. “But then it was like, ‘Now what?’” Mr. Friedman suggested she set up an advisory committee, think of the park as a series of galleries in a museum, and, most importantly, have art up all the time. “He said, ‘You shouldn’t just have a show for a few months and then go dark. Museums don’t go dark.’”

Mr. Friedman liked the park. “It’s not wild and woolly, it’s a Beaux-Arts plan,” he said. “The possibility of making special pieces there appealed to me.” So he opened his Rolodex. “When he got to Sol LeWitt, I said, ‘Wow, do you think Sol LeWitt would do something here?’” Ms. Landau remembered. “And he said, ‘Debbie, just call him. Here’s his number.’”

This isn’t that surprising, coming from a man who refers to Marcel Duchamp as “accessible.” In 1965, he interviewed Duchamp onstage at the Walker. “I had seen him a few times, I knew him from New York.” He and Mickey had spent time with him in Paris. “He was accessible. He was at the Marshall Chess Club. You’d pick up the telephone and say, ‘Mr. Duchamp, I’d like to talk to you.’ He’d say, ‘Why not now?’ So we’d meet at some drugstore or something, have a sandwich.”

In 2006, the year before LeWitt died, he displayed two major large new concrete sculptures in Madison Square Park. The following year brought stainless steel tree pieces by Roxy Paine and a film, projected on huge screens, by William Wegman, in which Mr. Wegman’s Weimaraners posed as park patrons and workers. There was an interactive light installation by Rafael Lozano-Hemmer; 2010 saw the biggest splash, that Anthony Gormley installation, the “boneheaded” one.

“He lives in this hell right now,” said Mr. di Suvero, “Everything he did was for the vision of others, and then he had that horrible irony of losing his vision.”

For decades, Mr. Friedman has suffered from macular degeneration; over time, it results in loss of eyesight. In 1959, the year after he became a curator at the Walker, he traveled to Abiquiu, N.M., to visit Georgia O’Keeffe, who was then in her 70s and whose work he wanted to include in an exhibition. He’d written her and gotten strongly worded rejections, so he showed up. She, too, it turned out, had the eye condition. She insisted he take off his glasses, and showed him a series of eye exercises. Then she took him to Ghost Ranch. “She scared me. I kept imagining my head as one of those parched skulls. I kept saying, ‘It’s very hot, Ms. O’Keeffe.’ She said, ‘You’ll get used to it.’” She agreed to participate in the exhibition.

He has fought the condition tooth and nail. He continues to write, by dictating to an assistant. There is the sense, even now, when one is around him, that artistic production, wherever it is to be found, will continue to afford improbably rewarding experiences. On a coffee table in his living room, like a still life, sits the catalog of the 2012 Whitney Biennial, next to a special pair of reading glasses. Squinting at the art world, he still sees it pretty clearly. “I love the idea that the Biennial is now a work in progress and is being redefined,” he said. “It will be very difficult for the Whitney to go back to a conventional Biennial, after this one.”

sdouglas@observer.com