Walter J. Leonard, right, with U.S. Circuit court Judge Leon Higginbothan, left, and historian John Hope Franklin in 1979. (AP)

Walter J. Leonard, a Harvard University administrator who was instrumental in devising one of the country’s earliest and most effective affirmative-action programs, which became a model for other universities around the country, and who later served as a college president in Tennessee, died Dec. 8 at a retirement facility in Kensington, Md. He was 86.

He had Alzheimer’s disease, his wife, Betty S. Leonard, said.

Mr. Leonard, a Howard University-trained lawyer, became an assistant dean and assistant admissions director at Harvard Law School in 1969. From the beginning, he sought ways to increase the presence of African American students and other minorities at the elite law school.

In 1971, he was named special assistant to Derek C. Bok, when Bok moved from dean of the law school to president of Harvard University. Mr. Leonard then took charge of an affirmative-action program at the law school.

He worked out a formula in which race was considered, among other factors, in the admission process. The Harvard Plan, as it became known, resulted in growing numbers of minority students and women at the law school and broadened the diversity of the university’s faculty and staff members.

Walter J. Leonard with actress Cicely Tyson at a White House state dinner in 1999. (Lois Raimondo/The Washington Post)

“His position was extremely delicate and difficult, and he carried it out with great distinction,” Bok told Harvard Law Today this month. “The atmosphere was tense and progress could not be as rapid as many of our students felt was necessary. Walter’s presence turned out to be a real blessing to all concerned.”

The Harvard Plan became a blueprint for affirmative-action efforts throughout the country, as universities aimed to reflect the country’s growing diversity. A continuing debate soon emerged, however, as critics called affirmative action a form of reverse discrimination. Nonetheless, Mr. Leonard’s Harvard Plan has withstood repeated legal challenges with few modifications.

In 1978, the U.S. Supreme Court upheld the principle of affirmative action in the landmark decision California v. Bakke while striking down the use of racial “quotas” to achieve diversity. In the Bakke decision, Supreme Court Justice Lewis Powell cited the Harvard Plan as an exemplary model to encourage diversity without making race the sole factor in college admissions.

(The Supreme Court is currently considering a legal challenge to affirmative action at the University of Texas.)

Walter Jewell Leonard was born Oct. 3, 1929, in Alma, Ga., and grew up in Savannah, Ga. His father was a railroad worker.

Mr. Leonard served in the Coast Guard in the mid-1940s, entering the service at age 15. His family said he was asked to leave what is now Savannah State University in 1949 after he led protests against a bus system that refused to transport black students.

In the 1950s, Mr. Leonard worked for the Navy Department in Washington, then lived in Atlanta, where he was a corrections officer and later a real estate developer. He studied at Morehouse College and Atlanta University before receiving a law degree from Howard University in 1968.

In 1977, Mr. Leonard was named president of Fisk University in Nashville. He found that the doors he opened for minority students at Harvard and other leading universities had created problems for Fisk and other predominantly black colleges, as enrollments fell and contributions dried up.

When Mr. Leonard took over at Fisk, the heat had been shut off in the dormitories because of unpaid bills.

Mr. Leonard raised millions of dollars for and offered to use his personal life insurance policy as collateral for a loan to keep the university afloat, but he steadfastly refused to sell the university’s art collection, valued at more than $10 million and including works by Toulouse-Lautrec, Picasso and Renoir.

“You don’t sell the car to pay the car note,” Mr. Leonard said in 1984. “Fisk without art would be like coffee without aroma. I insisted that we hold on to these valuable treasures.”

By 1983, enrollment had shrunk to about 650 from 1,600 a decade earlier, and the faculty gave Mr. Leonard a “no-confidence” vote. He clashed with some of the university’s biggest donors, who vowed not to give money to Fisk as long as Mr. Leonard was president.

The university’s trustees stripped Mr. Leonard of his day-to-day authority in October 1983, leaving him with little choice but to step down at the end of the school year.

“I simply cannot beg any longer,” he wrote in his resignation letter.

Mr. Leonard was a distinguished senior scholar at Howard from 1984 to 1986 and executive assistant to the governor of the U.S. Virgin Islands from 1987 to 1989. He was executive director of a nonprofit educational agency now called Communities in Schools from 1990 until his retirement in 1994.

He settled in Chevy Chase, Md., and was a member of St. Gabriel Catholic Church in Washington.

Survivors include his wife of 64 years, Betty Singleton Leonard of Chevy Chase; and a daughter, Angela M. Leonard, a history professor at Loyola University Maryland, of Baltimore. A son, Anthony C. Leonard, died in 2007.

Mr. Leonard was a visiting professor at many colleges across the United States and, for 13 years, was a fellow and visiting scholar during summer programs at the University of Oxford in England.

Despite holding positions at elite universities and expanding educational opportunities for African American students nationwide, Mr. Leonard never forgot that his first academic steps came at historically black colleges in the South.

He called them “necessary institutions, the bedrock of American culture.”