Sex discrimination involves treating someone (a job applicant or employee) unfavorably because of that person's sex. Sex discrimination is a form of employment discrimination that violates federal law—including Title VII of the Civil Rights Act of 1964 (42 U.S.C. §2000e).

In addition to these federal laws, states also have laws against sex discrimination in employment. These state laws are generally located in a state’s statutes—often in the labor code or employment-related statutes.

Discrimination against an individual because of gender identity—including transgender status or sexual orientation—is discrimination because of sex in violation of Title VII.

The law forbids discrimination when it comes to any aspect of employment, including hiring, firing, pay, job assignments, promotions, layoff, training, fringe benefits, and any other term or condition of employment.

For the regulations related to sex discrimination, see the Code of Federal Regulations, beginning with 29 CFR 1604.1.

In Missouri, sex discrimination in employment is prohibited under both federal and state law. Federally, Title VII of the Civil Rights Act of 1964 makes it illegal to discriminate based on sex in any aspect of employment, including hiring, firing, pay, promotions, and other terms or conditions of employment. This federal protection extends to gender identity and sexual orientation. The relevant regulations can be found in the Code of Federal Regulations at 29 CFR 1604.1. Additionally, Missouri state law, specifically the Missouri Human Rights Act (MHRA), also prohibits sex discrimination in the workplace. The MHRA applies to employers with six or more employees and covers many of the same aspects of employment as Title VII. It is enforced by the Missouri Commission on Human Rights. Employers in Missouri must comply with both sets of laws, and employees who experience sex discrimination have the right to file a complaint with the appropriate federal or state agency.