Twenty years ago this month, Anita Hill stepped into the glare of the national spotlight, testifying before the all-male Senate Judiciary Committee about the vulgar sexual advances she said she endured a decade earlier while working at two government agencies for Clarence Thomas, the nominee to the Supreme Court.

Those hearings brought into the open the problem of sexual harassment — an issue that millions of women privately recognized but rarely discussed. For many, having a way to define and label the behavior was empowering.

In the months and years afterward, recognition of the issue grew and tolerance of harassment in workplaces and on campuses shrank. The law changed, too. The month after the hearings, Congress passed a law that allowed sexual harassment victims to seek damage awards as well as back pay and reinstatement. It was signed by President George H. W. Bush, who had threatened to veto the act just a week before Ms. Hill testified.

Initial fears that Ms. Hill’s shoddy treatment by the Judiciary Committee would deter victims of sexual harassment from coming forward proved unfounded. The Equal Employment Opportunity Commission, where Ms. Hill worked for Mr. Thomas during his time as its chairman, saw a 50 percent increase in sexual harassment filings the year after the hearing. In the 2010 fiscal year, according to the commission, the number of such filings with the E.E.O.C. and state and local fair employment agencies totaled 11,717, compared with 6,883 in 1991.