Title IX, the landmark gender equity law passed as part of the Education Amendments of 1972, banned sex discrimination in federally funded education programs. Its protections would open doors for girls and women in admission, academic majors, teaching positions, vocational programs and individual classes, and help ensure equal access and treatment once they got in.

“This was during a time where there were a lot of barriers for women to progress or succeed in society,” says Karen Hartman, an associate professor at Idaho State University who has studied Title IX extensively. “The Educational Amendments Act, and specifically Title IX, was attempting to address some of those wrongs and provide more opportunities.”

Yet despite its broad aims and applications, Title IX is most famous for its impact on expanding opportunities for women and girls in sports. In 1972, there were just over 300,000 women and girls playing college and high school sports in the United States. Female athletes received 2 percent of college athletic budgets, while athletic scholarships for women were virtually nonexistent.

By 2012, the 40th anniversary of Title IX’s passage, the number of girls participating in high school sports nationwide had risen tenfold, to more than 3 million. More than 190,000 women were competing in intercollegiate sports—six times as many as in 1972. By 2016, one in every five girls in the United States played sports, according to the Women’s Sports Foundation. Before passage of Title IX, that number had been one in 27.

“There used to be a way to view women's sports [as] lesser than,” Hartman says. “But if you watch women's sports today, their competitive level with men is oftentimes on a similar playing field. We're seeing athleticism like we've never seen before.”

The roots of Title IX go back to the Civil Rights Act of 1964, which made it illegal to discriminate on the basis of race, color, religion or national origin—but made no mention of discrimination based on sex. Women were included in the Civil Rights Act only in Title VII, an amendment that addressed equal employment opportunity but did not apply to educational institutions, among other areas.

By the early 1970s, girls and women continued to face discrimination and unequal treatment in many areas of education. Female students were often barred from certain male-only courses or fields of study, including everything from wood shop and calculus to criminal justice, law and medicine. Some U.S. colleges and universities refused to allow women to attend, or established quotas that limited the number of female students regardless of how qualified they were compared to male applicants. Others denied tenure to female professors, or refused to hire them at all.

In 1972, President Richard Nixon signed the Education Amendments Act of 1972, which included Title IX, into law. Senator Birch Bayh of Indiana, who introduced the amendment in the Senate and helped guide the bill through Congress, called it “an important first step in the effort to provide for the women of America something that is rightfully theirs.”

By the time compliance with Title IX became mandatory in 1978, the law had already made an impact on sports. In a cover story that June, TIME reported that six times as many high school girls were participating in competitive high school sports than in 1970.

“Participation rates for women have exploded every single year since Title IX was passed in 1972,” Hartman says. “We see not only how sport has become more culturally acceptable for women to participate in, but how they also have increased their competitiveness.”

The law’s far-reaching impact could be seen at the 2016 Olympics in Rio de Janeiro, where American women dominated sports from gymnastics to basketball to swimming. That year saw the largest contingent of U.S. female Olympians in history, with a total of 292 women and 263 men. Back in 1972, only 90 women had joined the U.S. Olympic team of 428 athletes.

“It's kind of like ‘if you build it, they will come,’” Hartman says. “If you give opportunities, then you see how competitive and athletic all bodies can be, no matter if they're men or women.”

Organizations like the National Collegiate Athletic Association (NCAA) have challenged Title IX’s legality, while others have argued that it should apply only to educational programs that directly receive federal funds.

In 1984, the Supreme Court agreed with this interpretation in Grove City v. Bell, effectively removing Title IX coverage of athletics except for athletic scholarships. Passage of the Civil Rights Restoration Act of 1987 (over President Ronald Reagan’s veto) reversed that decision, and reinstituted Title IX’s broad coverage for any educational institution receiving any federal funds.

The 1990s and beyond have seen continued legal challenges to Title IX, as well as a number of lawsuits alleging the violation of its protections. “Over the decades since it's been passed, legal cases have tried to give more guidance for Title IX, and the Department of Education’s Office of Civil Rights created compliance elements for it,” Hartman says. “That path over 50 years has been bumpy….[and today] up to 80 percent of higher education institutions are still out of compliance.”

According to Hartman, controversy over Title IX often centers on misunderstandings of the law, such as the mistaken belief that it requires quotas, or the idea that has caused a decline in men’s sports. In fact, she says, participation rates for male athletes have increased consistently since Title IX’s passage. A special report issued for Title IX’s 40th anniversary in 2012 found that NCAA member institutions saw a net gain of nearly 1,000 men’s sports teams from 1988-2011.

In 2021, as part of a wave of lawsuits filed after U.S. colleges cut athletic programs due to financial pressures caused by the COVID-19 pandemic, the Clemson University men’s track and field and cross-country teams won a historic settlement for their claim of discrimination based on Title IX. As there were nearly an equal number of men and women athletes participating in sports at Clemson in 2019-20, the plaintiffs argued, the cuts meant the university was no longer providing an equitable number of opportunities under the law.

Hartman believes the case provides further evidence that Title IX—while its ultimate promise may remain unfulfilled—continues to make progress. “That’s the heart of a great anti-discrimination law,” Hartman says. “Something that’s going to bring men and women [together] to make sure there is equity.”