Labor unions

Evidence Rating  
Evidence rating: Scientifically Supported

Strategies with this rating are most likely to make a difference. These strategies have been tested in many robust studies with consistently positive results.

Disparity Rating  
Disparity rating: Potential to decrease disparities

Strategies with this rating have the potential to decrease or eliminate disparities between subgroups. Rating is suggested by evidence, expert opinion or strategy design.

Health Factors  
Date last updated

Labor unions are associations of workers organized to secure improved wages, benefits, and working conditions through collective bargaining. These associations are also called trade unions or referred to more broadly as organized labor. Employees can choose to join a union by paying membership dues. Democratically elected union leaders represent the employees’ interests in negotiations with their employer1. On their own, individual workers often have limited power to negotiate with their employer. By organizing, workers gain power to negotiate for fairer wages and benefits and increased input into workplace safety and operations, workers’ schedules, and management decisions, without fear of management retaliation. By withholding their labor (through strikes or threats to strike) workers can offset employers’ power, which is usually greater2. Such organizations exist in both the public and private sector, with workers able to join a union affiliated with their trade, industry, or company1. Most federal employees are also able to join unions3.

As of 2024, 26 states have Right-to-Work laws, which means that individuals employed in a unionized workplace are not required to join or pay dues to the union that represents them4. Member dues are how unions cover costs to represent workers4.

What could this strategy improve?

Expected Benefits

Our evidence rating is based on the likelihood of achieving these outcomes:

  • Improved health outcomes
  • Reduced fatal injuries
  • Increased health insurance coverage
  • Increased earnings
  • Increased pension coverage
  • Increased access to paid leave

Potential Benefits

Our evidence rating is not based on these outcomes, but these benefits may also be possible:

  • Increased political participation
  • Increased social connectedness
What does the research say about effectiveness?

There is strong evidence that labor unions in the U.S. directly and indirectly improve health for employees in unionized workplaces5 and reduce broader societal inequality2, 5. Unions increase employer-provided health insurance, reduce dangerous working conditions, increase federal safety inspections, and reduce fatal injuries, with the largest benefits in private sector unionized workplaces. Unions also increase wages and the likelihood that employees receive pensions, compared with non-union workplaces. Additional evidence is needed regarding the full extent of unions’ effects on health outcomes, as well as differences in benefits between public and private sector unions5.

Direct health impacts. For covered workers, unionization decreases fatal injuries in workplaces5. Rates of workplace fatalities had been declining for 20 years but began to increase again around 2008, coinciding with more states passing Right-to-Work legislation; such laws are associated with a decline in workplace unionization and a 14.2% increase in occupational fatalities, or ‘deaths on the job’6. Unions also directly improve health for covered workers by increasing employer-provided health insurance coverage, Occupational Health and Safety Association (OSHA) inspections, and by reducing dangerous safety and environmental hazards5. For example, unions may bargain to limit long working hours (more than 8) and swing shift work that includes days and nights, which can have significant negative impacts on workplace safety5, 7. More research is needed to understand unions’ effects on non-fatal injuries5, with some studies suggesting unionization increases non-fatal injuries8 while others suggest it reduces them9. Experts disagree about explanations, noting that unionized workplaces may be more likely to overreport accidents while non-unionized workplaces may underreport5.

Indirect health impacts. Unions increase workers’ knowledge of their right-to-refuse dangerous work, their right to know what chemicals they are exposed to in the workplace and the risks, and their entitlement to light duty after an injury, all of which appear to improve health5. Unions also appear to reduce excessive overtime, increase safety training, and increase access to workers’ compensation, paid sick leave, family leave, and vacation time5, 10. Some studies suggest that U.S. states with a higher union density (the percentage of workers in a trade who are union members), and states with more public sector unions, have been quicker to adopt paid parental and family leave policies11.

Wages and pensions. Union coverage increases wages for workers, especially those earning lower wages, compared to workplaces without unions, and increases the likelihood employers provide pensions5. Estimates vary, from union wages of 15% higher for public and private sector combined5 to a 7-10% wage increase in newly unionized private sector firms, which also may increase employer pension contributions by 20% on average10. In the public sector, collective bargaining by unions appears to increase the generosity and amount of pension contributions and benefits; generosity can include retirement age and service requirements to qualify for pensions, and how final average salary is calculated12. However, in the last 20 years, the value and generosity of state-managed pension plans in the U.S. has decreased and public employees’ contribution share has increased13. In broader society, labor unions appear to decrease income inequality and to improve wages and benefits for all jobs5. A study comparing the U.S., the UK, and France between 1970 and 2019 finds that income inequality, and thereby wealth inequality, increased most in the U.S., potentially linked to greater erosion of collective bargaining rights14.

Civic participation and support. Unions may increase social support and solidarity by encouraging members to come to meetings and share grievances with each other5, 15. A study of union contracts from the Pacific Northwest suggests that union contract language promotes health by focusing on elements such as income, access to health care, workplace safety culture, work-life balance, and democratic participation. In relation, contracts may state that employees can join union-sponsored legislative ‘lobby days’ on topics of interest or do political work while being paid by their employer15. Union contracts also often include restatements of health-promoting laws and policies, which may reinforce union representatives’ and covered employees’ knowledge of health-promoting regulations and protections15. Union membership may increase political activities such as voting, protesting, and belonging to other associations, particularly among individuals with less education, who often have lower levels of political participation16. Union membership may also increase political knowledge, both through materials directly provided to workers and workplace discussion17; a study of unions in European stable democracies suggests union members are more likely to engage in political activities and view democracy positively18.

Challenges from U.S. employers. In the U.S., employers often challenge unionization and collective bargaining. A study comparing U.S. and Canadian labor relations finds U.S. managers may hold less hostile attitudes toward unions – but suggest this could be because the U.S. model leads managers to perceive unions as lacking power. Experts note that the U.S. has a more sophisticated union avoidance industry than other countries, with firms able to hire experts (consultants, law firms, industry psychologists, and strike management firms) to advise them on how to curtail union organizing efforts, which has been common practice to resist unionization since the 1970s5, 19. Some U.S. law firms specializing in union avoidance offer their services to multi-national corporations and maintain offices in Asia, Europe, and Latin America20.

Recommendations. Experts describe multiple options for reforms to support a fairer balance of power between unions and employers in the U.S.19. In the U.S., this could mean keeping the existing system but strengthening laws protecting right to organize, penalizing employers who violate labor laws, and easing the processes and speed with which employees can exercise their rights to form, join unions, and collectively bargain19, 21.

Others propose that the U.S. consider transitioning to a more centralized structure for collective bargaining, where unions are organized by sector and negotiations happen with employer associations21, 22. These models are more common in European and Nordic countries and can increase employers’ and governmental support for unions since there is less localized negotiation -- and reduced conflict can mean large-scale cost savings22. Denmark’s ‘Flexicurity’ model, which has been an example in the European Union, has increased employer and governmental support for unions in Denmark by combining sectoral union-employer association bargaining with a three-part structure: employer flexibility in hiring and dismissing employees, union-administered unemployment insurance, and government-run job centers that support individuals in finding jobs quickly and receiving job education or retraining23, 24.

Models where unions offer or administer unemployment insurance also appear especially relevant to union membership stability. In countries with such models (‘Ghent’ systems), such as Sweden, Denmark, Finland, and Belgium, workers are more likely to join unions and periods with higher unemployment appear to increase union density22, 25. Changes in Finland and Sweden, including actions by more conservative governments to increase workers’ fees for the voluntary unemployment funds, appear to have caused unionization to decline22.

Other reforms view unions as a tool to reduce economic and health disparities. In Canada, some experts propose making union membership automatic for new workers, based on public support for this type of reform and the fact that declining union density and influence is associated with rising inequality26. Experts also recommend that public health practitioners raise awareness among policymakers that unions can support employees’ health, and that public health practitioners and unions partner to draft more sophisticated contracts with health-promoting features15.

How could this strategy advance health equity? This strategy is rated potential to decrease disparities: supported by strong evidence.

There is strong evidence that labor unions have the potential to decrease disparities in wage inequality among workers in covered workplaces, compared with workplaces without unions5, 44. In society at large, labor unions decrease overall societal income inequality2, 5 and improve wages and benefits for all jobs5.

Nearly two-thirds (65%) of individuals covered by private or public sector union contracts are women or minorities2, 5. In the public and private sector, unions raise wages more for workers who are Black and Hispanic than for workers who are white, compared with wages these groups earn in the greater labor market, decreasing disparities in income between the groups. Similarly, studies on public sector unions find coverage raises wages more for women than men. There appears to be less wage discrimination and, since at least the 1970s, less discrimination in general, toward women and minoritized groups in union-covered workplaces5. In general, union members who are white are more likely to support policies benefiting workers who are Black, and joining a union may reduce attitudes of racial resentment, compared to white workers not in unions. New union membership between 2010 and 2016 appeared to reduce such attitudes29. States with more public sector unions appear to adopt paid parental and family leave policies more quickly. Experts suggest this may be because a majority of public sector union members are women, who may influence their unions to prioritize family policy issues, which may affect state policy directions11.

Studies of the U.S. in the 1950s suggest that union membership, at its highest in U.S. history, was associated with the country’s lowest levels of wage inequality. Unions appear to have boosted wages most for individuals who are Black, as well as those with the lowest incomes and those with less education. These patterns were still evident in the 1970s, even as Civil Rights activism opened more unionized jobs to Black workers and as more educated white individuals moved to less unionized sectors44. Other studies suggest that if private sector unionization had not declined in the U.S., largely due to business opposition5, the wage gap between Black and white women workers would be 30% smaller because Black women were more likely to hold unionized jobs45.

Unions also experience workforce and demographic challenges in recruiting and retaining members. A multi-country comparison that includes the U.S. suggests that union density may be declining in part due to rising atypical employment (jobs that are part-time, fixed-term, or temporary). Studies suggest workers in atypical employment are less likely to join unions, possibly because of weaker ties to their workplaces, a view that union membership holds little benefit, and limited recruitment efforts by unions. Workers in standard full-time jobs appear more likely to join unions, but this type of work has become a smaller share of jobs22.

To strengthen union density and representation, experts recommend that unions expand recruitment efforts to include individuals in atypical employment, who are more likely to be women, as well as to women overall. Women’s union density (the percentage of women union members, out of the total employed) has surpassed men’s in some countries, but not in the U.S.22. Public sector and private sector unions could also broaden recruitment to reach individuals with varying levels of education, as those with more education appear more likely to join unions in the public but not the private sector. Experts also recommend that unions address anticipated demographic change, which will mean fewer workers replace those retiring, and falling union density. Experts recommend unions also focus on recruiting young workers and supporting them throughout their careers in the labor market22.

What is the relevant historical background?

Workers in the U.S. have been organizing and striking with others in their trade since at least the 1780s, for higher wages and improved working conditions46. In the late 1800s, the global Industrial Revolution meant that many individuals moved to cities as new technologies and processes for manufacturing emerged47. In the U.S., jobs in factories, sweatshops, and mines were characterized by long hours (12-hour days and a six-day workweek), dangerous environments, and poverty wages48. Workers formed unions to increase bargaining power for better conditions, but strikes were routinely met with intimidation and violence by employers, supported by the government, who sometimes sent troops to suppress strikes49 and ruled against unions in court50. Deadly disasters like the Triangle Shirtwaist fire in 1911 brought national attention to working conditions, but few protections were added for workers in response48.

The Department of Labor was created in 1913 but unions remained relatively weak until the 1930s48. Presidential support and legislation passed by Congress during the New Deal led to many gains for labor unions51, including the 1935 National Labor Relations Act which guaranteed private sector employees the right to unionize, collectively bargain, and strike, and established the National Labor Relations Board52. However, two years of large scale labor strikes and fear of communism after WWII led to the passage of the 1947 Taft-Hartley Act48, which ushered in “Right-to-Work,” allowing states to pass laws allowing individuals to work in unionized workplaces without belonging to the union, which would have long lasting consequences for union stability5. After its passage, unions largely quit negotiating over working conditions, focusing on hours, benefits, and wages -- which increased health risks alongside health coverage48.

By the 1960s, employers had increased working hours, including in jobs with dangerous conditions. Workers’ exposure to asbestos and coal dust led to a resurgence in occupational-related diseases. Labor worked with other groups as part of a broader movement to protect workers, consumers, and the environment, which led to the passage of laws including Coal Mine Health and Safety Act of 1969, the Occupational Safety and Health Act (OSHA) of 1970, and the Consumer Product Safety Act of 1972, as well as the creation of the Environmental Protection Agency48.

Union membership in the U.S. peaked in the 1950s, when approximately 33% of the workforce was unionized, mostly through private unions5. While private union membership began declining in the 1960s, public union membership (first allowed by Wisconsin in 1959) was increasing, and by the late 1970s nearly 33% of public workers were in a union5. The 1980s saw aggressive efforts by organized business to oppose unions, with support from the Reagan administration, and union membership continued to decline5. More recently, a growing movement by Republicans has focused on reducing public unions’ power53, exemplified in 2011 by Act 10 in Wisconsin, which eliminated most collective bargaining rights from public sector unions (excluding firefighters and law enforcement officers), required annual union recertification, banned auto-withdrawal of union dues, and reduced state obligations to pay for worker pensions and benefits, effectively decreasing workers’ take home pay54.

Unions began partnering with civil rights groups during the New Deal, and eventually endorsed the 1964 Civil Rights Act29, though early unions often excluded non-whites, and some supported racist immigration policies29. Many AFL unions excluded workers who were Black, but the Congress of Industrial Organization (CIO), founded in 1935, organized workers regardless of racial background49. In some cases, workers who were Black formed their own unions, such as the Brotherhood of Sleeping Car Porters55. When the American Federation of Labor and Congress of Industrial Organizations (AFL-CIO) emerged in 1955, it led to some conflicts based on race, and members who were Black had to address ongoing discrimination inside the organization through the 1970s56. The AFL-CIO began actively embracing racial, ethnic, and gender diversity in the 1980s29 and continues to investigate unions’ role in racial and economic justice49.

While most workers can organize into unions, some public-sector, agricultural, and domestic workers such as in-home health and child care workers, occupations historically filled by women and workers of color, are excluded from federal protections and are subject to state and local policies, which may prevent them from striking34.

Equity Considerations
  • Which workers in your community do not make a living wage? Are they represented by a union? Where can community members find information about their rights to form or join unions?
  • What barriers exist to forming unions in your community or organization? Does your state have Right-to-Work or other legislation in place limiting unions’ ability to collect dues for representation?
  • Who is opposed to unionization? How do they benefit?
  • How can public health and organized labor share data and resources to support aligned goals?
Implementation Examples

In the United States, most labor unions belong to one of the national federations of unions, the American Federation of Labor and Congress of Industrial Organizations (AFL-CIO) and Strategic Organizing Center (SOC). In 2023, 10% of workers (14.4 million) belonged to unions27, compared to around 90% in Iceland and around 65% in Sweden and Denmark in 201928. In the U.S., 32.5% of public-sector workers (7.0 million) are unionized, including police, firefighters, and teachers; and 6% of those in the private sector (7.4 million), particularly in utilities, transportation and warehousing, educational services, and motion picture and sound recording industries. The least unionized groups include finance, professional and technical services, and food service27. Workers who are Black are the most likely to be in unions (11.8%), followed by those who are white (9.8%), Hispanic (9.0%), and Asian (7.8%)27; Latinos are the fastest growing segment of new members29. Union membership is lowest in the South27.

Support for unions has been increasing since 200930: In 2023 67% of Americans supported unions30, with support strongest among voters under 3031. In 2023, 26 states and Guam had Right-to-Work laws, but in the same year Michigan repealed theirs, the first state to do so in decades32. Additionally, in 2022 Illinois voters passed the Workers’ Rights Amendment, a constitutional amendment which essentially bans Right-to-Work laws, guaranteeing collective bargaining and organizing rights for all workers33.

In 2018 and 2019, pre-pandemic, the number of workers striking was at the highest level since the 1980s, but still 80% lower than at the historic peak in the U.S., and 70% lower than the early 1970s. COVID-19 curtailed work stoppages, but numbers began rising again in 2022 and continued into 2023, with several high profile strikes or threats to strike, from Starbucks baristas to Hollywood actors and writers to health care workers34. Strikes by health care workers are more common in other countries than the U.S.35, but U.S. hospital work stoppages involving 1,000 or more workers are up. Fifteen took place between January 2022 and October 2023, including at Kaiser Permanente, when approximately 75,000 workers went on strike for 3 days, the largest health care strike in recent U.S. history36. Approximately 13% of U.S. healthcare workers, including nurses, physicians, dentists, technicians, support staff, advanced practitioners, and therapists, belonged to unions in 202137. Unions representing industries such as mining continue to lobby for reduced hazardous working conditions. In 2023 the U.S. Department of Labor proposed a rule to reduce silica dust exposure in coal mining, which can cause debilitating lung disease, after a decades-long effort by unions38.

The Service Employees International Union (SEIU) helped create and fund the Fight for $15, the campaign to increase the minimum wage to $15 and unionize workers39. Fight for $15 began in 2012 with 200 fast food workers in New York City striking to demand $15 per hour and the right to unionize and is now active in over 300 cities around the globe40. While the movement for unionization has spread in the service industry, large corporations such as McDonalds and Starbucks continue to fight against unionization efforts41.

In 2023 the NLRB simplified union recognition processes, ruling that unions may be recognized as a bargaining representative with either a simple majority of members designating the union as their representative, or through an official election42.

National-level federations can be affiliated with global labor unions; for example, the AFL-CIO is affiliated with the International Trade Union Confederation, which represents more than 200 million workers worldwide43.

Implementation Resources

Resources with a focus on equity.

Worker.gov-Forming a union - Forming a union at a non-union workplace. Worker.gov.

NLRB - National Labor Relations Board (NLRB).

NLRB-Basic steps - National Labor Relations Board (NLRB). Basic steps to forming a union (infographic).

Labor action tracker - Labor action tracker. Cornell University School of Industrial and Labor Relations (ILR); University of Illinois Urbana-Champaign School of Labor & Employment Relations.

Fightfor15 - Fight for $15.

AFL CIO-Form a union - American Federation of Labor and Congress of Industrial Organizations (AFL-CIO). Form a union.

UFCW-Start a union - How to start a union. United Food and Commercial Workers International Union (UFCW).

Footnotes

* Journal subscription may be required for access.

1 Britannica-Trade Union - Britannica Money. Trade Union.

2 US Treasury-Unions 2023 - U.S. Department of the Treasury (US Treasury). Labor unions and the middle class. 2023.

3 NLRB-Right to Strike - National Labor Relations Board (NLRB). The right to strike.

4 NCSL-RTW - National Conference of State Legislatures (NCSL). Right-to-work resources.

5 Leigh 2021 - Leigh JP, Chakalov B. Labor unions and health: A literature review of pathways and outcomes in the workplace. Preventive Medicine Reports. 2021;24:101502.

6 Zoorob 2018 - Zoorob M. Does “right to work” imperil the right to health? The effect of labour unions on workplace fatalities. Occupational and Environmental Medicine. 2018;75(10):736-738.

7 Wagstaff 2011 - Wagstaff AS, Sigstad Lie J-A. Shift and night work and long working hours - A systematic review of safety implications. Scandinavian Journal of Work, Environment and Health. 2011;37(3):173-185.

8 Donado 2015 - Donado A. Why do unionized workers have more nonfatal occupational injuries? ILR Reivew. 2015;68(1):153-183.

9 Economou 2015 - Economou A, Theodossiou I. Join the union and be safe: The effects of unionization on occupational safety and health in the European Union. Labour. 2015;29(2):127-140.

10 Knepper 2020 - Knepper M. From the fringe to the fore: Labor unions and employee compensation. Review of Economics and Statistics. 2020;102(1):98-112.

11 Engeman 2021 - Engeman C. When do unions matter to social policy? Organized labor and leave legislation in the US states. Social Forces. 2021;99(4):1745-1771.

12 Brookings-Frandsen 2017 - Frandsen BR, Webb M. Public employee pensions and collective bargaining rights: Evidence from state and local government finances. Washington, D.C.: Brookings Institution; 2017.

13 NBER-Abashidze 2021 - Abashidze N, Clark RL, Craig LA. Reductions int he generosity of state and local employee pensions: comparison of plans with and without Social Security coverage. National Bureau of Economic Research (NBER). 2021: Center Paper NB21-09.

14 Tippet 2022 - Tippet B, Onaran Ö, Wildauer R. The effect of labor’s bargaining power on wealth inequality in the UK, USA, and France. Review of Income and Wealth. 2022:1-27.

15 Hagedorn 2016 - Hagedorn J, Paras CA, Greenwich H, Hagopian A. The role of labor unions in creating working conditions that promote public health. American Journal of Public Health. 2016;106(6):989-995.

16 Kerrissey 2013 - Kerrissey J, Schofer E. Union membership and political participation in the United States. Social Forces. 2013;91(3):895-928.

17 Macdonald 2021 - Macdonald D. How labor unions increase political knowledge: Evidence from the United States. Political Behavior. 2021;43:119-142.

18 Turner 2020 - Turner T, Ryan L, O’Sullivan M. Does union membership matter? Political participation, attachment to democracy and generational change. European Journal of Industrial Relations. 2020;26(3):279-295.

19 Campolieti 2013 - Campolieti M, Gomez R, Gunderson M. Managerial hostility and attitudes towards unions: A Canada-US comparison. Journal of Labor Research. 2013;34:99-119.

20 Logan 2019 - Logan J. The new union avoidance internationalism. Work Organisation, Labour & Globalisation. 2019;13(2):57-77.

21 Brookings-Broady 2020 - Broady K, Macklin M, O’Donnell J. Preparing U.S. workers for the post-COVID economy: Higher education, workforce training and labor unions. Washington, D.C.: Brookings Institution; 2020.

22 Schnabel 2013 - Schnabel C. Union membership and density: Some (not so) stylized facts and challenges. European Journal of Industrial Relations. 2013;19(3):255-272.

23 Denmark-Flexicurity - Denmark.dk. Working in Denmark. The Danish labour market: Flexicurity.

24 Gorg 2022 - Görg H, Hornok C, Montagna C, Onwordi GE. Employment to output elasticities and reforms towards flexicurity: Evidence from OECD countries. Bulletin of Economic Research. 2022;75(3):641-670.

25 Lindellee 2022 - Lindellee J, Berglund T. The Ghent system in transition: Unions’ evolving role in Sweden’s multi-pillar unemployment benefit system. Transfer. 2022;28(2):211-227.

26 Harcourt 2022 - Harcourt M, Gall G, Wilson M. Making union membership the default option in Canada: Would it be supported and effective? Relations Industrielles. 2022;77(4).

27 US BLS-Unions 2024 - U.S. Bureau of Labor Statistics (BLS). News release: Union members - 2023. 2024.

28 OECD-TUD - OECD Data Explorer. Trade Union Density (TUD).

29 Frymer 2020 - Frymer P, Grumbach JM. Labor unions and white racial politics. American Journal of Political Science. 2020;65(1):225-240.

30 Gallup-Saad 2023 - Saad L. More in U.S. see unions strengthening and want it that way. Gallup. 2023.

31 Pew-Gramlich 2021 - Gramlich J. Majorities of Americans say unions have a positive effect on U.S. and that decline in union membership is bad. The Pew Charitable Trusts (Pew). 2021.

32 Cappelletti 2023 - Cappelletti J. Michigan becomes 1st state in decades to repeal ‘right-to-work’ law. PBS NewsHour. 2023.

33 EPI-Sherer 2022 - Sherer J. Illinois workers’ rights amendment sets new bar for state worker power policy. Economic Policy Institute (EPI). 2022.

34 EPI-Bivens 2023 - Bivens J, McNicholas C, Poydock M, Sherer J, Leon M. What to know about this summer’s strike activity: What’s spurring the rise in labor actions? Economic Policy Institute. 2023.

35 RAND-Fischer 2023 - Fischer SH. Why health care workers are striking. RAND Corporation. 2023.

36 HFMA-Hut 2023 - Hut N. Healthcare labor union activity gains steam: The consequences for hospitals and health systems. Healthcare Financial Management Association (HFMA). 2023.

37 Ahmed 2022 - Ahmed AM, Kadakia K, Ahmed A, Shultz B, Li X. Trends in labor unionization among US health care workers, 2009-2021. JAMA. 2022;328(24):2404-2411.

38 US DOL-Silica 2023 - U.S. Department of Labor (U.S. DOL). Mine Safety and Health Administration. U.S. Department of Labor announces proposed rule to reduce silica dust exposure, better protect miners’ health. 2023.

39 Guardian-Greenhouse 2022 - Greenhouse S. ‘The success is inspirational’: The fight for $15 movement 10 years on. The Guardian. 2022.

40 Fightfor15 - Fight for $15.

41 Pollard 2023 - Pollard A. Fast food workers are unionizing, but some of the biggest chains in the country are fighting to stop them. Business Insider. 2023.

42 NLRB-Recognition - National Labor Relations Board (NLRB). Board issues decision announcing new framework for union representation proceedings.

43 AFL CIO-Global - American Federation of Labor and Congress of Industrial Organizations (AFL-CIO). Global labor unions and federations.

44 NBER-Callaway 2017 - Callaway B, Collins WJ. Unions, workers, and wages at the peak of the American Labor Movement. National Bureau of Economic Research (NBER). 2017: Working Paper 23516.

45 Ahlquist 2017 - Ahlquist JS. Labor unions, political representation, and economic inequality. Annual Review of Political Science. 2017;20(21):1-24.

46 Perlman 1922 - Perlman S, Ely RT, eds. A history of trade unionism in the United States. New York: Macmillan Publishers; 1922.

47 LOC-Industrial America 1876-1900 - Library of Congress. U.S. history primary source timeline: Rise of industrial America, 1876 to 1900, overview.

48 Rosner 2020 - Rosner D, Markowitz G. A short history of occupational safety and health in the United States. American Journal of Public Health. 2020;110(5):622-628.

49 AFL CIO-Solidarity - A brief history of labor, race, and solidarity. American Federation of Labor and Congress of Industrial Organizations (AFL-CIO): labor commission on racial and economic justice.

50 NLRB-Pre-Wagner - National Labor Relations Board (NLRB). Pre-Wagner Act labor relations.

51 LOC-Labor 1929-1945 - Library of Congress. U.S. history primary source timeline: Great Depression and World War II, 1929 to 1945, labor unions during the Great Depression and New Deal.

52 NLRB-Wagner Act - National Labor Relations Board (NLRB). 1935 passage of the Wagner Act.

53 EPI-Shierholz 2024 - Shierholz H, McNicholas C, Poydock M, Sherer J. Workers want unions, but the latest data point to obstacles in their path. Economic Policy Institute (EPI). 2024.

54 WPR-Act 10 lawsuit 2023 - Unions file new lawsuit challenging Act 10 collective bargaining law. Wisconsin Public Radio (WPR). 2023.

55 LOC-BSCP - Library of Congress. Research guides: Brotherhood of sleeping car porters union formed.

56 Cassedy 1997 - Cassedy JG. African Americans and the American labor movement. Prologue magazine, special issue: Federal records and African American history. 1997;29(2).