A Labor Union is composed of employees who act collectively to influence and bargain with management and business.
When interacting with management, a labor union uses several tactics and tools to get the best result. The most famous -- and most extreme -- example of a union action is striking, or walking off the job in protest; striking is not seen as often today, since businesses don't want the bad press, and they want to be seen as accommodating.
More often, unions bargain with management to present their requests. Bargaining on behalf of all employees is central to a union's role, since they seek fair and equal treatment for everyone. Depending on size, one or more union representatives will meet with one or more members of management in closed or open meetings. Negotiations to honor or refuse requests is performed almost as haggling, with each side seeking the best result; lawyers are often involved to resolve important legal issues. Almost all union bargaining today ends with an equitable arrangement between parties. Once an agreement is reached, it becomes legally binding, and can be referred to as such by both sides if further legal action is taken.