Collective Bargaining Agreements 
What is collective bargaining?
"Collective bargaining is the mutual obligation of employers' and employees' representatives to meet at reasonable times and confer in good faith with respect to wages, hours, standards of productivity and performance, and other terms and conditions of employment, or the negotiation of an agreement, or a question arising under an agreement."
From "A Guide to the Massachusetts Public Employee Collective Bargaining Law", published by the Commonwealth of Massachusetts Labor Relations Commission. The full document can be found
here.