Agent Ed Kleven died Wednesday night at the age of 72 after a long battle with multiple sclerosis and leukemia.

Probably you have never heard of Ed. But you know his work. You know his clients and friends. They have peppered and painted the sports landscape around these parts since the mid 1970s.

Eddie negotiated with George Steinbrenner and Howard Hughes. He represented Tony Conigliaro, John Havlicek, Bucky Dent, Gorman Thomas, and Richie Hebner. While rolling his wheelchair around the halls of the Dana Farber Cancer Institute in December, he wrapped up a new ESPN deal for the great Tim Kurkjian.

Ed Kleven was a character from another era, but to his dying days, he was still working, still connecting folks, still being a friend and uncle.

He was a one-man shop, working out of his modest home in Brookline. He was the antithesis of IMG, Scott Boras, and the corporate giants who promote their players as “brands.’’ Eddie’s guys did not have a contract with their agent. They had a handshake. They had his word. That’s all they needed.

He grew up in Haverhill, son of a shoe manufacturer. His dad had some connections, and one of Eddie’s prized possessions was a photo of him as a little kid seated next to slugger Ted Williams at a Jimmy Fund luncheon.

Like Teddy Ballgame, Eddie had a love of baseball and a lifelong dedication to childhood charities. Every Christmas for the last 40 years, Ed’s friends received cards from the Joey Fund and/or Dana Farber, notifying them that contributions had been made in their name by Edward Kleven.

Eddie went to Governor Dummer (now Governor’s Academy) and played all the major sports in the Independent School League. Groton School coach Jake Congleton forever remembered a teenage Ed Kleven beating Groton with a rainbow jumper from deep in the corner.

“Pure luck,’’ said agent Ed, smiling at the memory.

He was not one for bragging, and loathed those who would call attention to themselves. They were “frauds.’’

Eddie graduated from Tufts in 1966 and took his first job teaching fifth-graders in Carlisle. He had little patience for it.

“Most of the time I just showed movies,’’ he said. “I am sure many of my students would agree teaching was not for me.’’

In 1966, he went to work as road manager for The Kingsmen, the ultimate one-hit wonder band. The Kingsmen recorded “Louie, Louie,’’ a three-chord ditty that became a monster hit and was later immortalized in “Animal House.’’ It was rumored that the lyrics were dirty, but a two-year FBI investigation determined only that the lyrics were “unintelligible,’’ which was just fine with Eddie and the Kingsmen.

It was during this time that he was hired by a Hub promoter to take care of West Coast band and national sensation The Byrds on a tour of small New England venues.

“It was a disaster,’’ recalled Kleven. “They had hit the big time after agreeing to the deal and didn’t want to play here. I picked them up in my woody station wagon and took them to some fleabag motel on Storrow Drive and they were bitching and moaning the whole time. David Crosby was a real bust-out.

“They stiffed the promoter when I took them to the Hampton Beach Casino. The next day, I went to pick them up for another gig and the girl behind the desk said, ‘The Byrds flew the coop and went back to LA!’ ’’

In 1968, Kleven hit the road with Dionne Warwick (“after three years listening to ‘Louie, Louie’ 320 days a year’’) and served as her manager for seven years. It was during this time that he negotiated with the elusive Howard Hughes concerning Mr. Hughes’s offer to bring Ms. Warwick to Las Vegas for a private concert.

“He seemed like a nice man, but we needed a private jet,’’ said Kleven. “He had jets. We got the jet.’’

In 1975, Eddie started representing baseball players. The list is endless. Bill Castro, Jim Slaton, Jim Colborn, Jim Spencer, Ken Berry, Ken McMullen, Don Money, Bill Travers, Sam Mejias, Billy Conigliaro, Tom Poquette, Darrell Porter, Jack Brohamer. Eddie cherished a letter he got from Steinbrenner after hammering out a deal that guaranteed Spencer would be in the lineup against righty starters.

Eddie kept at it through all of baseball’s changes, and at the start of a new century, he was representing Japanese pitcher Shigetoshi Hasegawa.

“He was so loyal and committed to me and my family,’’ Colborn said Thursday. “He’d come to my kids’ birthday parties. He was an uncle to them. I think he was like that with a lot of us.’’

In 1983, after Tony Conigliaro suffered a massive heart attack, Eddie organized a fund-raiser at Symphony Hall and solicited help from Warwick, Frank Sinatra, and Joe DiMaggio.

“That was a challenge,’’ he recalled. “Sinatra and DiMaggio hated each other.’’

Eddie’s media client roster was formidable. It started with his Brookline next-door neighbor Peter Gammons. It led to John Dennis, Mike Lynch, Bob Neumeier, Karl Ravech, Jack Harper, Paula Lyons, Wendi Nix, Wally Brine, Jayson Stark, Jackie MacMullan, Ian Thomsen, Leigh Montville, Chuck Wilson, Larry Johnson, Beth Germano . . . and more. Too many to name.

His first roommate out of college was Joe O’Donnell, the concession king who tried to buy the Red Sox in 2001. Other roommates were Billy Conigliaro and Bob Montgomery. Eddie never married, but not for lack of candidates. He was diagnosed with MS in the mid ’70s and devoted the rest of his life to being a great friend and dedicated uncle.

In his final years, he spent a lot of time with his sister Gail and her husband, Richard Gelb, and doted on his niece, his nephew, and their children. He also had lunch every week with Bruins vice president Nate Greenberg, longtime Boston Garden executive Steve “The Commander’’ Nazro, and Massachusetts Associate Justice Mitch Sikora.

After Eddie died Wednesday night, Clark Booth (a.k.a. “The Cardinal’’) wrote, “If the measure of a man is the quality of his friends, Eddie was rich beyond measure.’’

Amen.

Dan Shaughnessy can be reached at dshaughnessy@globe.com

There will be a service for Edward Kleven Friday morning at 11 a.m. at the Stanetsky Memorial Chapel at 1668 Beacon Street in Brookline. Donations in his name can be made to the National Multiple Sclerosis Society, Massachusetts Chapter, 101A 1st Ave., Suite 6, Waltham 02451.