The four agencies that govern relations between unions and employers:

National Labor Relations Board (NLRB) http://www.nlrb.gov

The National Labor Relations Board is an independent federal agency created by Congress in 1935 to administer the National Labor Relations Act, the primary law governing relations between unions and employers in the private sector. The statute guarantees the right of employees to organize and to bargain collectively with their employers or to refrain from all such activity. Generally applying to all employers involved in interstate commerce – other than airlines, railroads, agriculture, and government – the Act implements the national labor policy of assuring free choice and encouraging collective bargaining as a means of maintaining industrial peace. Through the years, Congress has amended the Act and the Board and courts have developed a body of law drawn from the statute.

National Mediation Board (NMB) http://www.nmb.gov/

The National Mediation Board (NMB), established by the 1934 amendments to the Railway Labor Act of 1926, is an independent agency that performs a central role in facilitating harmonious labor-management relations within two of the nation's key transportation modes – the railroads and airlines.

Federal Labor Relations Authority (FLRA) http://www.flra.gov

The Federal Labor Relations Authority (FLRA) is an independent agency responsible for administering the labor-management relations program for Federal employees world-wide, approximately 1.3 million of whom are exclusively represented in more than 2,200 bargaining units. Its mission is to promote stable and constructive labor-management relations that contribute to an efficient and effective government.

Public Employment Relations Commission (PERC) http://www.perc.wa.gov/

The Washington State Legislature created the Public Employment Relations Commission in 1975 to provide for "uniform and impartial...efficient and expert" administration of state collective bargaining laws, to "ensure the public of quality public services."