Congress has enacted three major laws that govern labor-management relations. The first law, the Railway Labor Act (RLA), was enacted in 1926. The RLA applies to railway and airline carriers. In 1935, Congress passed the National Labor Relations Act (NLRA), which applies to private sector employers other than railroad and airline carriers. Congress enacted the Federal Service Labor-Management Relations Statute (FSLMRS) in 1978. The act applies to most federal employees. This report provides a brief history, including major amendments, of each of the three statutes. The discussion of each law begins with an overview of the statute and then discusses in more detail the key statutory provisions of the law and how the law is administered and enforced. This report uses specific "terms of art" relevant to these three acts. Appendix A defines these terms. Appendix B provides a list of acronyms used in the report. Appendix C compares the provisions of the three statutes. By the late 19 th century, the railroad industry had a significant impact on the U.S. economy. It helped connect the coasts, making settlement of the western United States much easier. Farmers were able to ship their goods to cities hundreds of miles away, and consumers were able to purchase products made in factories across the nation. The railroad industry was also a major consumer of U.S. goods. It used over 75% of the steel produced in the United States and a large portion of the United States' extracted coal, and was the nation's primary employer. As the public began to depend on railroads and their regular availability, railroad workers also began to unionize. Because the nation grew dependent on railroads, labor-management disputes that grew into work stoppages adversely affected the nation's welfare. Enacted in 1926, the Railway Labor Act (RLA) continued a pattern of federal attempts at regulating labor relations in the industry. The act was the product of an agreement between industry and labor. The statute was intended to help maintain labor-management peace in the railway industry and thereby avoid work stoppages that could carry with them adverse economic and social effects. The act's five major purposes are to: prevent any interruption to commerce or to the operation of any carrier; ensure employees the right to organize or join a labor union; ensure railway carriers and employees the right to select bargaining representatives without interference from the other party; provide timely settlement of disputes over rates of pay, rules, or working conditions; and provide timely settlement of disputes growing out of grievances or over interpretation or application of existing union contracts. To accomplish these goals, Congress established a system based on collective bargaining between labor and management, relying on mediation facilitated by the newly created National Mediation Board (NMB) and voluntary arbitration if neither collective bargaining nor mediation worked. The original RLA called for parties to establish by agreement special adjustment boards (SBAs) to resolve disputes over contract interpretation or application concerning changes in rates of pay, rules, or working conditions. These boards could be national, regional, or local in scope and would typically be composed of an equal number of carrier and employee representatives. If an adjustment board was unable to resolve a dispute because of a deadlock, the dispute could be referred to the Board of Mediation. In the 1934 amendments, Congress created the National Railroad Adjustment Board (NRAB), which has jurisdiction over contract interpretation and administration disputes that cannot be resolved through direct negotiations. If the NRAB is deadlocked, it selects a referee to make an award in the dispute. A referee is a neutral person who sits with the NRAB as a member and makes an award in the dispute at issue. Congress later replaced the Board of Mediation with the NMB, which can resolve disputes between parties concerning changes in rates of pay, rules, working conditions, and any other dispute not referable to NRAB. Congress also strengthened the RLA's provisions that allow carriers and employees to select representatives freely and without interference from each other. It added language specifically stating that employees have the right to organize and bargain collectively and added a provision requiring that a majority of employees in a craft or class must support a union before it is recognized as their representative. Additionally, the amendments prohibited carriers from denying or questioning an employee's right to organize or join a union and tasked the NMB with investigating representation disputes. The amendments also provided for both civil and criminal means to enforce the RLA's provisions. Congress explicitly prohibited carriers from unilaterally changing pay rates, rules, and working conditions and added a "status quo" provision, which prohibits changes to pay rates, rules, and working conditions for 30 days after parties are released from the NMB's services. Finally, the definition of "carrier" was broadened to include companies that perform operations integral to railway transportation but not already covered by the act. In 1936, Congress extended most of the RLA's provisions to commercial airline carriers that operate in interstate or foreign commerce and airlines that transport mail for, or under contract with, the U.S. government. Although the airline industry was relatively new in 1936, Congress acknowledged that it was part of the national transportation system that was vital to the economic well-being of the nation and that it too would need mechanisms to assist in dispute resolution and avoiding work stoppages. Although the National Labor Relations Act (NLRA), which covers most private sector employees, was enacted in 1935, labor wanted airline carriers to be included under the RLA, because it believed the RLA's mediation/arbitration dispute resolution mechanisms provided more flexibility for the constantly changing, fledging industry. Between 1951 and 1981, the RLA was the subject of much congressional action. The major changes enacted are discussed below. In 1951, Congress amended the RLA to allow carriers and unions to enter into union security agreements. These agreements require employees to pay union dues equal to the cost of representation as a condition of employment. However, under a union security agreement, employees are not required to become formal members of the union. State right-to-work laws that prohibit or restrict union security agreements are preempted by the RLA. In 1966, Congress amended the RLA to provide for Public Law Boards (PLBs) that can be established upon the request of either party. Unlike an SBA, the parties do not need to agree on the creation of a PLB. PLBs are composed of one person selected by the carrier and one person selected by the union. Each selected board member is compensated by the carrier or union that selected them. If these selected board members deadlock on an issue, they designate a neutral third party to decide the dispute. If the selected board members are unable to agree on a neutral party, the NMB designates the neutral party. The neutral party is compensated by the NMB. Finally, in 1981, Congress established emergency procedures for certain publicly funded and operated carriers that provide commuter rail services. The RLA was most recently amended in 2012 during the 112 th Congress as part of the Federal Aviation Administration (FAA) Modernization and Reform Act of 2012. Under these amendments, for the NMB to conduct an election or otherwise certify a union for a craft of unrepresented employees, the NMB must receive, along with an application for certification, authorization cards signed by at least 50% of the employees in the craft or class seeking representation. Before this amendment, those parties filing an application for certification were required to include authorization cards signed by at least 35% of employees in the craft or class seeking representation. The 2012 amendments also changed the rules for runoff elections. Previously, only the names of the two unions that received the most votes in the first election were on the runoff ballot. If more employees voted not to have a union than voted for either of the two unions that received the most votes, the runoff ballot did not include the choice of not being represented by a union. Under the 2012 amendments, a runoff ballot has the two choices, including the choice not to be represented, that received the most votes in the initial election. The 2012 amendments also mandated periodic NMB evaluations and audits. The RLA seeks to prevent labor-management disputes that could interrupt railroad and airline service and harm the economy. It grants certain rights to both workers and carriers, seeks to prevent practices that could frustrate a peaceful worker-carrier relationship, and provides mechanisms for workers and carriers to resolve disputes. To achieve these goals, the RLA regulates the labor-management relationship between workers and carriers in the railway and airline industries. It provides parties with a standard process for choosing a union to act as an employee representative in the collective bargaining process and details which individuals can participate in the process. Once a union is chosen, the RLA governs which subjects workers and unions can negotiate. The RLA also regulates how workers, carriers, and unions should behave towards each other during the union selection and collective bargaining processes and prohibits certain unfair actions. The RLA provides for several entities to administer and enforce its provisions. The National Mediation Board (NMB) is the primary agency charged with administration and enforcement of the act. It also provides mediation services to parties that cannot reach a resolution in a dispute. The National Railway Adjustment Board (NRAB) is an NMB tribunal that hears and decides (arbitrates) grievances in the railway industry. Additionally, in the railway industry, the RLA allows parties to a dispute to establish their own arbitration tribunals, known as Special Boards of Adjustment (SBAs), or a single party to request that the NMB create a Public Law Board (PLB) to arbitrate the dispute. Various System Boards of Adjustment (System Boards), created jointly by labor and management, arbitrate disputes in the airline carrier industry. Finally, if an unresolved dispute threatens to substantially interrupt commerce, the President can create a Presidential Emergency Board (PEB) to investigate and aid in the resolution of the dispute. The RLA regulates the collective bargaining rights and duties of carriers and employees in the railway and airline carrier industries.