(FORTUNE Magazine) – When in 1994 Forbes magazine profiled Bronson Ingram, head of Ingram Industries, a multibillion-dollar Nashville distribution conglomerate, it dismissed the chairman's wife in one line: "Wife Martha is the grande dame of Nashville's social and performing arts scene." A year later, Bronson Ingram was dead from cancer, and Martha Ingram became chairman of the private company her husband had built. In the subsequent months, the world would learn what company insiders had known all along--"wife Martha" was no philanthropic dilettante. She was the quintessential steel magnolia who, for all her gentility and modesty, was willing to stand up to those who thought her husband's death would create a power vacuum at Ingram Industries.

When she took the helm, many thought she would stay quietly in the background. More particularly, few expected her to monkey with the company's crown jewel, Ingram Micro, the biggest computer wholesaler in the world. The unit was firmly under the control of CEO Chip Lacy, the man who had built it up from next to nothing into a then $8 billion powerhouse.

Ingram Micro was growing at a phenomenal rate--327% in five years--and the baby was draining its parent's precious resources. Not long before Bronson's death, Lacy had pushed the chairman to take the company public in order to generate more capital, but he had refused. "My father didn't want to be answering to a bunch of analysts every day," says oldest son Orrin. Neither did Orrin and his brothers, John and David. They had worked in the family businesses since they were 14 and wanted to stay involved.

Martha was caught between trying to do what was right for Ingram Industries and its 12,000 employees and protecting her family's personal and financial interests. The solution she persuaded everyone to accept: Spin off Ingram Micro as a public company, and let the family continue to run the rest of Ingram's Nashville-based businesses as private companies.

It was a bold stroke for any executive, but it hardly registered on the business radar--perhaps because of distribution's inherent lack of sex appeal. The Ingrams have made their fortune not by producing things but simply by acting as the pipeline between manufacturer and seller. By definition, it is a nearly invisible operation. Ingram Micro was so obscure that few recognized the enormous company until its initial public offering catapulted it to No. 113 on last year's FORTUNE 500 list.

Prior to that, Martha Ingram was perhaps the country's most anonymous billionaire and most underappreciated businesswoman, but she likes it that way. She does not flaunt her accomplishments and speaks in a deceptively grandmotherish tone more suited to reading Mother Goose than cutting deals. Do not be fooled.

If Martha Ingram was "as tough as she needed to be," according to her son John, then her husband, Bronson, was indomitable. "He was tough as nails," says Bob Doolittle, who as a managing director of investment bank J.C. Bradford advised the Ingrams on several occasions. When Bronson Ingram died in June 1995, he left a $10 billion conglomerate that in addition to Ingram Micro operated an inland barge company, a video distributor, a book wholesaler, and a small insurance business (see chart). Providing warehousing and distribution is a capital- intensive business of razor-thin margins, but early on Ingram developed remarkable logistical efficiencies, becoming a leader in customer service and fast, accurate delivery. Once the system was in place, Ingram realized he could distribute almost anything.

To understand the depth of Bronson Ingram's power, it's helpful to understand Nashville. While famous to the outside world for its country music stars with their guitar-shaped pools and rags-to-riches lifestyles, Nashville has long been run by old-money businessmen whose power base consists of a troika of institutions: the Chamber of Commerce, the Belle Meade Country Club, and the Vanderbilt Board of Trust. They wield their influence discreetly, shunning attention. It's a town where "nice people" still get into the paper only when they're born, when they're married, and when they die.

Bronson, in his day, dominated this scene. If Martha Ingram had wanted to fade into the background as a Belle Meade belle she certainly could have; her role was neatly carved out. But, says Doolittle, this is not the path she chose. "If she appears as the gracious Southern hostess who dutifully followed her husband, once you get to know her you realize nothing could be further from the truth," he says.

FORTUNE spoke with Ingram recently--the day after her 62nd birthday. She was in a reflective mood, and spoke at length about business, family, and herself. It is easy to see how you could underestimate her toughness as she admits, laughing, "Young women who come in for advice are usually very disappointed to learn all I wanted to do was be a wife and mother." And yet it is in this same voice that Martha Ingram states unequivocably her answer to the question: What do you like most about business? "I like winning."

Her life has straddled these two very different ambitions since she was a young girl in Charleston. Her father owned a broadcasting company and made it clear to young Martha, the oldest of his three children, that she should be ready to take over the business should something happen to him. "It seems particularly odd in today's world," says Ingram, "because women frequently feel there's a glass ceiling. But my father never said anything to me about being a woman or how odd it would be to be in the business world."

However, it was as a young mother (she had four children in five years) in Nashville that Martha discovered her competitive streak. She began an eight-year crusade to raise money and legislative support to build the Tennessee Performing Arts Center, or TPAC. In 1979, after Martha secured a $5 million endowment for TPAC, her husband asked her to join him at Ingram Industries.

She immersed herself in the company and its businesses, and by 1981 she had become a member of the board. Although her role was director of public affairs, it was clear to other board members that she was well versed in all the company's operations.

In addition to overseeing corporate donations--Ingram gives 2% of its pretax income to charity--she became a go-between for management and the company's employees. She installed a toll-free line (still there) that rings in her office for folks who want to discuss problems that cannot go through normal channels. "I knew," says Martha, "that I was part of a team with Bronson. He was certainly the big decision-maker, but he bounced a lot off me.... I definitely shared with my husband the sense of wanting to win, of wanting to accomplish whatever it was we set out to do."

It wasn't exactly a leap, then, for her to step into the chairman's position upon her husband's death. "There was no question that she should be elected," says former Ingram Distribution CEO Phil Pfeffer, now president of Random House.

Nevertheless, she had a lot to learn, and quickly. And she had to start by addressing how to finance the remarkable growth at Ingram Micro.

Essentially, Ingram Micro serves two constituencies: the producers of computer products, such as IBM and Microsoft, and the resellers and retailers who sell the computer products to businesses and individual customers. With the exception of build-to-order companies such as Dell, the vast majority of manufacturers warehouse and distribute through Ingram Micro and other wholesalers.

CEO Lacy invested heavily in automation and computerization; by 1995 the company controlled about 20% of the distribution market. In the process, he developed a reputation in the industry for his temper (he was called the Tasmanian Devil by a trade publication), and he wanted Ingram Micro to go public on his terms. According to sources familiar with the situation, he hungered for complete autonomy, demanding that Martha Ingram place her and her four children's shares (over 60% of the company) in a trust, to be voted by the management. "He forgot the golden rule," says Bob Doolittle. "The one with the gold rules."

Martha Ingram stood her ground and Lacy resigned in May 1996. Says Pfeffer: "Accepting Lacy's resignation was one of the most difficult types of decisions a business person has to make, and she didn't flinch. I give her total credit."

Ingram, for her part, likens her conflict with Lacy to "a marriage that had gone really well and then it hit a snag and we just decided we could not live together any longer." She adds, "I still have the highest regard for Chip."

Nevertheless, observers of the computer distribution channel were shocked. Most thought that Ingram Micro was nothing without Lacy and that no investor would pay for Lacy-less Micro stock. But Martha immediately began interviewing replacements and, in conjunction with the Ingram Industries board, selected Jerre Stead, a former AT&T executive, to be CEO in August 1996. The IPO proceeded as planned that November, with 20 million shares of Ingram Micro offered at a price of $18 a share.

Stead made his reputation as a rising star at AT&T by adopting "delight the customer" as a battle cry. He removed office doors and renamed managers coaches. (His Micro business card reads "Head Coach.") He won kudos for his management style, but when he was put at the helm of NCR, he was unable to make that disastrous acquisition work for AT&T.

However, he appears to be the right person to run Ingram Micro. Analysts have rewarded the company with continual buy ratings since the IPO, and the stock has had a steady rise. Wall Street has long been wary of computer distribution stocks, largely because of their low margins. In 1996, Ingram Micro earned a paltry 88 cents a share, or $111 million in net income, on sales of $12 billion. In this business, though, revenue numbers are the key indicator of strength--the bigger Ingram gets, the more favorable the pricing it can negotiate.

Bill Cage, an analyst at J.C. Bradford, believes that competition in the computer distribution industry is going to winnow out the small players until what's left is "a Coke and Pepsi situation." You can guess who'd play Coke. With the stock currently trading at $28.5, the Ingram family's stake is worth $2.4 billion. By standing her ground, Martha Ingram had done what she likes to do most: win.

Back in Nashville, meanwhile, the family had to sort out the rest of the company. Their holdings were complicated, tied up in trusts and Bronson's estate. One thing was clear: All three sons couldn't operate the family businesses by committee. David, 34, the youngest son, asked to go his own way. He had been president of Ingram Entertainment, the video distribution arm, since 1994 and wanted to head his own company. "I had strong opinions and was strong-willed. I said to my brothers, 'Hey y'all, why don't I do my own thing? I'll be out of your hair and then we won't have to compete for resources.' " Earlier this year, Ingram Entertainment was spun off as a separate private company in which David holds a 95% stake. It broke the $1 billion barrier in gross sales last year.

At Martha's suggestion, in December 1995 the board elected Orrin, 37, and John, 36, co-presidents of the still-private Ingram Industries, which in its post-spinoff form encompasses Ingram Marine, the inland barge and sand-dredging business; Ingram Book Group, which includes the nation's largest book wholesaler; and Ingram Insurance, which insures Ingram affiliates and owns a small automobile insurance company called Permanent General that caters to high-risk drivers. This reorganized company had 1996 revenues of $1.5 billion. The Ingrams' daughter, Robin, 31, also has a stake in Ingram Industries. Although she is not actively involved, her husband oversees venture capital investments for the company.

The earnest, straightforward Orrin is clearly passionate about his charge, the barge business, which he loves because "your word is your bond. I like that deals worth thousands of dollars are agreed to over the telephone. It's a business you can touch and understand." However, the barge business is by all accounts a mature one. Ingram plans to grow through strategic acquisitions such as the recent purchase of the marine assets of Occidental Chemical, which brought the total Ingram fleet to 1,800 barges and 62 towboats. Last year Ingram Marine posted revenues of over $235 million.

The real growth at Ingram Industries will probably come from the book group, which is headed by John, the more, well, bookish, of the brothers. He estimates that revenues for 1997 will top $1.5 billion and hopes to see $2 billion by 2000.

Although its growth has not been as spectacular as Ingram Micro's, the book group has come far from its days as the lowly state book depository. Bronson brought in managers who saw how retailers were struggling to keep books in stock, placing orders with hundreds of different publishers and sometimes waiting weeks for the books to arrive. With Ingram, retailers can place one order, receive one shipment, and be billed on one invoice, even if the titles come from many different publishers. It has seven warehouses and offers next-day service to 95% of the population. Largely because of Ingram's market penetration, wholesalers now handle about 25% of distribution to the retail book market, up from 10% 20 years ago.

In this business, with margins so low that every penny counts, Ingram has set itself apart by providing superior customer service. Says Larry Kirshbaum, CEO of Warner Books: "Their business is infused with tender loving care."

Martha Ingram is somewhat coy about her continued involvement with Ingram Micro. She holds a seat on the board, as do her sons David and John. Martha and her four children are among a group of select insiders to hold Micro's class B shares, which have ten times the voting power of the publicly traded class A shares. With this extra leverage, the Ingrams have about 75% of the voting power. That will change in November 2001, the five-year anniversary of the splitoff. At that point the class B shares will convert to class A shares and be worth one vote each.

Martha seems content with Ingram Micro now. "I think that during our lifetimes we'll stay interested in the company," she says. She emphasizes that she is not involved in the day-to-day operations. "Jerre Stead is on his own," she insists. Chip Lacy, meanwhile, has been named CEO of Micro Warehouse, a computer reseller. He will remain on the Ingram Industries board through December of this year, although beyond that no decision has been made, according to Martha Ingram. Lacy did not return calls from FORTUNE.

It's possible that Ingram will take more of a back seat now that her family's holdings seem secure. She is currently on the boards of Weyerhaeuser (a timber company that Bronson's great-grandfather helped found), First American Bank, and medical products giant Baxter International, as well as a myriad of nonprofit boards. But anyone who declares her love of winning as forthrightly as she does will no doubt keep at least one hand in the family business.

Many in Nashville still do not fully understand her role at Ingram Industries, and her success has been isolating, according to some. "I don't think she has a lot of friends she can confide in," says Jake Wallace, chairman emeritus of insurance broker Willis Carroon. "That comes with the territory. When you've got it all--when you're attractive, rich, and capable, that creates jealousies."

Perhaps Nashville will never recognize the contributions of Martha Ingram in the business arena. According to Wallace, "It's difficult in this town to attribute to the wife of an owner the amount of credit to which she may be entitled, because that hasn't been the tradition."

It may be difficult for Martha too: "First I had a father who thought I could do anything, and then a husband who made me believe I could as well. I've always been terrified they would find out I was inadequate," she says. Judging by her success, she need never worry about that.