Employment law is a broad category of laws—statutes, case law (court opinions), rules, and regulations—that govern the relationship between an employer and an employee. Employment law includes state laws that only apply to employer-employee relationships in a given state, and federal laws that apply to employer-employee relationships in all states.

In Missouri, employment law encompasses a variety of state statutes and regulations that govern the employer-employee relationship, in addition to federal laws that apply nationwide. State-specific laws cover matters such as minimum wage requirements, which as of 2023 is $12.00 per hour, and will increase annually with inflation. Missouri law also addresses issues like discrimination in the workplace, workers' compensation, and unemployment benefits. The Missouri Human Rights Act prohibits employment discrimination based on race, color, religion, national origin, ancestry, sex, disability, age (in employment), and familial status (in housing). Federal laws that apply in Missouri, as in other states, include the Fair Labor Standards Act (FLSA), which sets standards for minimum wage and overtime; the Occupational Safety and Health Act (OSHA), which ensures safe working conditions; the Americans with Disabilities Act (ADA), which prohibits employment discrimination against individuals with disabilities; and the Family and Medical Leave Act (FMLA), which entitles eligible employees to take unpaid, job-protected leave for specified family and medical reasons. Employers in Missouri must comply with both state and federal regulations to ensure lawful treatment of employees.