[Excerpt] The persistence of gender-based wage disparities—commonly referred to as the pay or wage gap—has been the subject of extensive debate and commentary. Congress first addressed the issue more than four decades ago in the Equal Pay Act of 1963, mandating an “equal pay for equal work” standard, and addressed it again the following year in Title VII of the 1964 Civil Rights Act. Collection of compensation data and elimination of male/female pay disparities are also integral to Labor Department enforcement of Executive Order 11246 (initially issued by President Lyndon Johnson), which mandates nondiscrimination and affirmative action by federal contractors. During the last several decades, initiatives to strengthen and expand current federal remedies available to victims of unlawful sex-based wage discrimination have been taken up in Congress. This report begins by presenting data trends in earnings for male and female workers and by discussing explanations that have been offered for the differences in earnings. It next discusses the major laws directed at eliminating sex-based wage discrimination as well as relevant federal court cases. The report closes with a description of pay equity legislation that has been considered or enacted by Congress in recent years.