Donald Dell is a Washington institution.

His resume reads as though it were written for a novel: Washington tennis phenom, student at the elite Landon School, Yale and University of Virginia law school, friend of the Shrivers and Kennedys, political operative, world traveler, undefeated captain of the U.S. Davis Cup team (that’s more tennis), and a revolutionary sports agent who represented legends such as Arthur Ashe, Stan Smith and Jimmy Connors.

The thing that intrigues me about Dell is that he didn’t burn out and loaf around country clubs after his tennis years. He used those skills to build a network, which in turn created business and social opportunities that have sustained his success over his 72 years.

I’ve had an amazing, wonderful life,” said Dell, who has lived on a 49.6-acre farm in Potomac since 1972.

He used his tennis contacts to launch in 1969 what became today’s Legg Mason Tennis Classic, an annual rite of Washington summer that starts in a couple of weeks.

After founding ProServ in the 1970s, he went on to become one of the biggest sports agents of his time. At its height, ProServ had 300 employees and 12 offices and represented about 250 athletes who grossed the firm more than $15 million a year.

ProServ suffered a serious setback when Dell’s assistant, David Falk, departed with a pair of key clients named Michael Jordan and Patrick Ewing.

Dell eventually sold ProServ for $25 million, then bought parts of it back, only to sell it again to Lagardere Unlimited, where he now serves as group president in charge of TV deals, events and tennis.

I never tire of hearing about the importance of networking, which I once considered a dirty word. Herewith is some advice from Dell and from his book, “Never Make the First Offer,” regarding the secrets of networking:

 -Make friends.

Dell uses Under Armour founder Kevin Plank, another Washington area native, as an example of someone who has “worked at every relationship. What Kevin has done, and what I think is the most basic aspect of achieving business success, is to create opportunities to get to know people out [italics his] of the office, out of the normal parameters of the business relationship, and outside mutual comfort zones.”

- Make friends of their friends.

Dell met FedEx founder Fred Smith through a friend who had owned the Memphis Racquet Club in Tennessee, where FedEx is headquartered. Dell, who was ranked as the top tennis doubles player in the United States for 1961 and 1962, played a doubles match with Smith and two others. They became friends, and Dell later represented FedEx in its $205 million naming rights deal with the Washington Redskins.

-Find mentors.

Dell had two big mentors in his life: tennis great Jack Kramer and the late Sargent Shriver of Potomac, who was the Democratic candidate for vice president in 1972. Shriver called Dell to ask him to coach Shriver’s son Bobby in tennis.

Later, on a visit to the family compound in Hyannisport, Dell, a lawyer at Hogan & Hartson at the time, asked Shriver whether he could take him up on a job offer that Dell had refused a few years earlier.

“His exact words were ‘Yes, sure.’ I became his special assistant, and he became my mentor for life.”

- Give advice (carefully).

Dell once told a young executive at American Express that his company was a “sleeping giant” that “has gotten too old and too fat.”

Years later, on a visit to the offices of American Express, chief executive Ken Chenault greeted Dell with: “The sleeping giant has awakened!”

Chenault was the young executive.

- Don’t keep score.

Dell’s client and close friend Arthur Ashe discovered a tennis star in Cameroon named Yannick Noah and asked Dell to help him. Dell made a phone call that led to all-expenses-paid training and education for Noah, who went on to win the 1983 French Open.

Noah returned the favor years later, when Noah’s son, Joakim, asked Dell to represent him for his NBA career.

- Massage your network.

Dell believes in sending personal notes. He dropped a line to movie producer Arnon Milchan after reading a magazine profile of the producer of “Pretty Woman” and “L.A. Confidential.” Milchan responded with a swift phone call.

“You are trying to keep your relationships update, current and enjoyable.”

- Do your homework.

After losing out to another agent for the chance to represent University of Virginia star Ralph Sampson, Dell learned an important lesson.

“I spent a year recruiting Sampson’s coach, Terry Holland. My competitor spent the year recruiting the mother,” Dell said. “Later, I found out to my chagrin that the mother, not Ralph, was the decision maker. I thought it would be a layup.”

- Show no fear.

This one is simple: An unsolicited telephone call to insurance giant Geico (a short walk from Dell’s office) led to Geico’s purchase of a suite for the Legg Mason Tennis Classic, which eventually led to a big sponsorship deal. Like the Nike ad: Just do it.

- Do good work.

I hear Garrison Keillor say this on his National Public Radio show.

Dell’s company hit a financial crisis in 1996 and he needed an urgent influx of money. He persuaded a member of the hugely wealthy French Dreyfus family to write him a seven-figure check, which put ProServ back on a firm financial footing.

“To this day, I know that if I had a reputation for being greedy or less than honest, Robert [Dreyfus] wouldn’t have written me that check.”

- Do good works.

The Legg Mason Tennis Classic, one of the top 20 tennis tournaments in the world, has raised $15 million for children over the years. Dell founded the tournament and gave it to the Washington Tennis and Education Foundation. He has run the tournament for the past 41 years, which has generated handsome returns to Dell’s company.

“Charities are definitely a networking opportunity, but it is important to get involved with charities that you feel strongly about.”

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