Collective Bargaining Agreements are contracts between an employer and a union or group of employees in one or more bargaining units and typically contain details on wages, benefits, and working conditions. The contract usually has a set number of years that it will be in force. The agreements often include specific policies and procedures that dictate how employees and management must act on a variety of issues, including promotions, overtime, the grievance process, union membership requirements, employee discipline, and other working conditions. In a few states, collective bargaining agreements supersede conflicting state law.