A teachers’ union is a labor union (an organized group of employees) that represents teachers or educators in contract negotiations (for salaries, tenure, paid time off, and other terms of employment) with schools or school districts. Teachers’ unions are said to engage in collective bargaining—bargaining or negotiating on behalf of all teachers—rather than individual teachers negotiating their own employment terms.

The rights of workers to form unions, strike, bargain collectively, and engage in other work-related activities are provided by the federal statute known as the National Labor Relations Act of 1935 (NLRA). The NLRA also prohibits unions from trying to force workers to join a union and prohibits employers from retaliating against workers who exercise their union rights.

The NLRA supersedes many state laws but it does not apply to employees in the public sector—including public school teachers. Some states have laws that prohibit collective bargaining for public employees (Georgia, North Carolina, South Carolina, Texas, Virginia) and many states have laws that make it illegal for public employees to strike.

In Florida, teachers' unions operate under state-specific regulations, as the National Labor Relations Act (NLRA) does not apply to public sector employees, including public school teachers. Florida law allows for collective bargaining for public employees, including teachers. The Florida Public Employees Relations Act governs labor relations between public employers and employees, including the right to collective bargaining. This act establishes the framework for how teachers' unions can negotiate contracts with school boards. However, while Florida permits collective bargaining, it has restrictions on the right to strike for public employees. Specifically, Florida Statutes prohibit strikes by public employees, classifying them as illegal and potentially leading to penalties such as fines, imprisonment, and termination of employment. Therefore, while teachers in Florida can organize into unions and engage in collective bargaining for better terms of employment, they are not legally permitted to strike as a form of protest or negotiation.