Trade unions, also known as labor unions in the United States, are organizations of workers in a common trade who have organized into groups dedicated to improving the workers' work life. A trade union generally negotiates with employers on behalf of its members, advocating for improvements such as better working conditions, compensation and job security. These unions play an important role in industrial relations -- the relationship between employees and employers.
The origins of trade unions can be found in guilds and fraternal organizations composed of people practicing a common trade, which date back hundreds of years. However, the modern conception of trade unions, in which unions represent a specific set of workers in negotiations with employers, dates back only to the 18th century. Membership in unions only became widespread in the United States and Europe in the 19th century.
Trade unions are generally organized by various trades. For example, in the United States, coal miners have their own union, the United Mineworkers Association, as do plumbers and pipefitters, who are considered similar enough to be grouped together. Trade unions are organized by trade based on the idea that a union grouped around people who perform similar tasks are more effective than those composed of workers practicing disparate skills.
In industrial relations, trade unions represent the interest of their members. By contrast, an employer represents his own interests, as well as the interests of those with financial stakes in the company. However, because both trade unions and employers can only earn a livelihood through the continued viability of the businesses that they work for and own, both parties will defend the interests of their industry.
The advocacy of trade unions has provided a number of improvements in the working conditions of many workers. For example, in the coal industry, advocacy by the UMA has led to safer working conditions for coal miners. However, given trade unions work in the interests of their members specifically, rather than the companies that employ these workers, unions can sometimes advocate policies that, while beneficial to workers in the short term, may harm the company's long-term health.
According to Bernhard Ebbinghaus, a professor at the Industrial Relations Research Institute and European Union Center at the University of Wisconsin, Madison, the role of trade unions changed significantly in the last decades of the 20th century. As union membership declined due to structural changes in the economy, unions became more active in maintaining vestiges of the welfare state. This includes resisting privatization of public institutions and roles, and advocating for public benefits for a country's citizens.