In this section we provide introductory sources for the history of organized labor generally and offer an introduction to the larger topic; other pages in this guide will provide some resources related to specific some unions. However, we have included below material related to the Industrial Workers of the World (IWW), sometimes referred to as the "Wobblies," an international labor union founded in Chicago in 1905. We have not included many biographies of labor leaders, instead we are including a few sources that contain biographical sketches on multiple leaders and we have included some directories. 

An important part of the history of labor history are the laws and court cases. They will often be mentioned in the resources provided, and can be researched on their own. Bureau of Labor Statistics covered Labor law highlights in Monthly Labor Review, but we have included a few that were particularly important to mention.

• Transportation Act of 1920. This law, sometimes referred to as the Esch–Cummins Act (Pub.L. 66-152, 41 Stat. 456), established the Railroad Labor Board (RLB) and was designed as a means of settling wage disputes between railway companies and their employees. The Board was abolished by the Railway Labor Act of 1926.
• Railway Labor Act of 1926. This law (May 20, 1926, ch. 347, §1, 44 Stat. 577) set in place a system for disposition of disputes between carriers and their employees and protects the right of employees to organize and bargain collectively.
• National Labor Relations Act 1935 Act. This law was signed on July 5, 1935 and created the National Labor Relations Board (NLRB) an independent agency and is the primary statute which allows the right of private sector employees to organize into trade unions and allows them to engage in collective bargaining and organize strikes. It is also referred to as the Wagner Act (Pub.L. 74-198, 49 Stat. 195).
• Fair Labor Standards Act. This law, often seen as FLSA (Pub.L. 75–718, ch. 676, 52 Stat. 1060), was signed in June 1938 and includes several labor related provisions including the right to a minimum wage, overtime pay for working more than forty hours a week, and provisions related to child labor.
• Labor Management Reporting and Disclosure Act 1959. This law provided for reporting and disclosure of certain financial transactions and administrative practices of labor organizations and employers. It is also referred to as the Landrum-Griffin Act. (Pub.L. 86-257, September 14, 1959, 73 Stat. 519-546).
• NLRB v. Jones & Laughlin Steel Corp. This Supreme Court decision upheld the constitutionality of the National Labor Relations Act of 1935.
• NLRB v. J. Weingarten, Inc. This Supreme Court decision held that an employee in a unionized workplace has, under the National Labor Relations Act, the right to request the presence of a union steward during any management inquiry if that employee reasonably believes it may result in discipline.
• Steelworkers Trilogy. This was actually a series of Supreme Court decisions (Steelworkers v. American Manufacturing Co., Steelworkers v. Warrior & Gulf Navigation Co., and Steelworkers v. Enterprise Wheel & Car Corp.) over the legal statutes related to arbitration.
• Janus v. American Federation of State, County, and Municipal Employees, Council 31. This Supreme Court decision concerns the ability of unions to collect fees from non-members. This decision relates to Abood v. Detroit Board of Education.

Books, Periodicals, and archival collections can be found in the subpages of this part of the guide.