Before the emergence of trade unions, it was difficult for employees to seek action against unfair treatment by their employers (Warner, 2012:133) Employees were having difficulties at work since the employers’ words were final, therefore, getting poor pays and working in poor conditions. With the emergence of trade unions, the employees were able to acquire better pays and their working conditions were improved. Trade unions represented the employees, protected them from exploitation, helped in the implementation of laws and policies that protected the employees, and campaigned for improved payments (Ewing, 2005:1). This essay will discuss the main functions of trade unions and examine how effectively they can achieve their goals in the modern-day employment relationship.The Employment Relations Act of 2008 describes a trade or a labor union as a registered or unregistered organization of people, whose main objective is to ensure the ordinance of employment relations between workers and employers (Employment Relations Act 2008, 2008:3). In the contemporary world, governments and employers are fully aware of the significance of trade unions, as failed negotiations can lead to various actions, such as, overtime bans and strikes, which stagnates development. Employers tend to avoid such situations as they lead to low productions, therefore, translating to unmet demand and losses. However, trade unions in the United Kingdom have experienced many changes that have arisen due to political and economic factors. This owes to the fact that employers have restructured the labour market, as many industries have been privatised, temporary employment and the use of contracts have increased and the workforce has been downsized (McKenzie, 2010:5). Globalization has also led to the changes experienced in the operations of many trade unions. Many companies have been internationalized, therefore, acquiring workers from foreign countries,which has also complicated the trade unions’ roles (Fernie and Metcalf, 2005:3).