I wanted to say that many large companies that also have a union have a grievance committee.
At AT&T the employees can submit a written grievance to the grievance committee in order to get resolution on a conflict that the employee was having.
The grievance committee is made up of a member of management that looks at the issue and tries to solve the problem in the most just and equitable way.
However, if the employee is not satisfied with the results that the manager provided, the problem gets escalated to a superior manager and can be reversed. This is called a grievance appeal.
For example, if an employee wanted to request two weeks off in January, but the immediate supervisor declined the request even though the employee not only bought a cruise for that timeframe but there was nothing in his union contract that stated that the month of January was blocked off for time off.
The matter went to a grievance committee and the manager in charge decided to allow the employee to take the time off because if not he knew that it would be overturned upon appeal because the manager was making an arbitrary decision that was inherently unfair.
This is why true conflict resolution also has to be fair because if not it can backfire.