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 Kansas, teachers' unions operate within the framework of state statutes rather than the National Labor Relations Act (NLRA), as the NLRA does not apply to public sector employees, including public school teachers. Kansas does allow collective bargaining for public employees, including teachers. The Professional Negotiations Act, K.S.A. 72-5413 et seq., governs the collective bargaining process for teachers in the state. This act requires school districts to negotiate with recognized or certified teacher organizations on matters such as terms and conditions of professional service. However, unlike some states, Kansas does not prohibit public employees from striking, but such actions can have legal and professional consequences. It's important for teachers and their unions to be aware of the specific provisions and limitations outlined in Kansas state law when engaging in collective bargaining and other union activities.