Utility Workers Union of America
AFL - CIO Local 127

As contract negotiations go on, the union may report back to the membership what items the parties have agreed to, and where the conflicts are. Sometimes members will be allowed—or even encouraged by the union—to sit in on bargaining sessions. If you can, take the opportunity to see firsthand how the union presents the employees’ point of view, and how the employer responds to the union’s agenda. It can be a real eye opener to witness the employer’s representatives “just say no” to things you know are totally reasonable. And it sends a useful message to the other side, too, when they see union members willing to take the time to show up and visibly support their bargaining team. 
—Adapted from The Union Member's Complete Guide, by Michael Mauer