In 1978, Ann Hopkins joined the Washington office of Price Waterhouse, which at the time was one of the country’s “Big Eight” accounting firms. She was, by all accounts, one of the company’s top management consultants.

She developed computer systems for clients and was responsible for winning the firm’s most lucrative contract, a project with the State Department worth up to $44 million. Job evaluations praised her as “a terribly hard worker” and “one of the very best.”

In 1982, she was the only woman among 88 candidates for partnership at Price Waterhouse. When she didn’t get the job, she learned that the firm’s reasoning had little to do with her work and more to do with how others perceived her womanhood. She resigned from the firm. Then, in 1984, she filed a job-discrimination lawsuit under Title VII of the Civil Rights Act of 1964.

Ms. Hopkins, who died June 23 at her home in Washington at 74, later told The Washington Post that she had “no choice but to sue. I had to do this as a matter of principle.”

Her case ended up going to the U.S. Supreme Court, changing the way courts view gender-based discrimination in the workplace.

The case

Ms. Hopkins’s lawyers argued that her male colleagues at Price Waterhouse considered her “too macho” and insufficiently ladylike. She was called “pushy” and “overbearing” and was said to need “a course in charm school.”

She smoked, drank beer and did not take her husband’s last name. She once rode to a job interview on her motorcycle.

A sympathetic male boss, who had recommended Ms. Hopkins for promotion, explained that the company’s hierarchy thought she should “walk more femininely, talk more femininely, dress more femininely, wear makeup, have her hair styled and wear jewelry.”

Federal Judge Gerhard A. Gesell ruled in Ms. Hopkins’s favor in 1985 on grounds of “discriminatory stereotyping of females,” noting that “comments influenced by sex stereotypes” were key factors in denying Ms. Hopkins the partnership.

Gesell did not, however, grant Ms. Hopkins’s request for $1.2 million in damages or to be reinstated to her old job. She continued to pursue her case until it was eventually taken up by the Supreme Court. In support of Ms. Hopkins, the American Psychological Association filed a supporting brief, citing more than 100 studies on stereotyping by gender.

In 1989, the Supreme Court ruled 6 to 3 that an employer had to demonstrate that its hiring decisions were based on merit, not on discriminatory notions, including those related to gender.

“In forbidding employers to discriminate against individuals because of their sex, Congress intended to strike at the entire spectrum of disparate treatment of men and women resulting from sex stereotypes,” Justice William J. Brennan Jr. wrote in his majority opinion. “An employer who objects to aggressiveness in women but whose positions require this trait places women in an intolerable and impermissible Catch-22: out of a job if they behave aggressively and out of a job if they don’t. Title VII lifts women out of this bind.”

It was the first time the court ruled that gender stereotyping was a form of discrimination.

Her case became the underpinning of a second generation of gender-discrimination litigation, often involving gay and transgender people.

Becoming partner and the ‘lost years’

After another year of courtroom hearings, Gesell issued a second ruling that forced Price Waterhouse to give Ms. Hopkins her partnership — seven years after it was denied. She also received more than $370,000 in back pay.

Price Waterhouse, which later became PricewaterhouseCoopers, developed a “hypersensitivity to issues of diversity because of Ann’s presence,” Fred Tombar, a former colleague, said in an interview.

“She was a partner and was in a position to insist that the company respect diversity as a value,” Tombar said. “She was a pioneer.”

Ms. Hopkins retired in 2002. In her 1996 memoir, “So Ordered: Making Partner the Hard Way,” she wondered “what might have happened if I had been a partner during those lost years.”

“Would I have risen higher in the ranks to a position where I could have more effectively influenced the firm to cherish diversity? Would some of the men I worked for have been working for me? I don’t know. What I do know is I never compromised on what I valued or believed.”

The cause of Ms. Hopkins’s death was acute sensory peripheral neuronopathy, a fast-developing nerve disorder of unknown origin.

Ms. Hopkins’s marriage to Tom Gallagher ended in divorce. Survivors include two children, Tela Gallagher Mathias of Germantown, Md., and T. Gilbert Gallagher of Washington; a sister; a brother; and five grandchildren. A son, Peter Gallagher, died in 2000.

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