Union busting is a term used by media, labor organizations, and others to describe a wide range of activities undertaken to disrupt or prevent the formation of trade unions. Union busting tactics can refer to both legal and illegal activities, and can range anywhere from subtle to violent. Labor laws differ greatly from country to country in both level and type of regulations in respect to their protection of unions, their organizing activities, as well as other aspects. These laws can affect topics such as posting notices, organizing on or off employer property, solicitations, card signing, union dues, picketing, work stoppages, striking and strikebreaking, lockouts, termination of employment, permanent replacements, automatic recognition, derecognition, ballot elections, and employer-controlled trade unions. Article 23 of the Universal Declaration of Human Rights (UDHR) declares that everyone has a right to form and/or join a trade union. The provision is, however, not legally binding and has, in most jurisdictions, no horizontal effect in the legal relation between employer and employees or unions.
Following the repeal of the Combination Laws in 1824, workers were no longer prohibited from forming labor organizations or collective bargaining, although significant restrictions remained. In 1832 the Friendly Society of Agricultural Labourers was formed in Dorset to challenge declining wages. The members of the organization agreed to only work for wages greater than a certain amount. In 1834 a landlord complained, and key members were charged and convicted under laws prohibiting the swearing of secret oaths. The sentence of seven years penal transportation to Australia prompted a movement to defend the members, known as the Tolpuddle Martyrs (referring to the village where the organization originated), who were eventually released in 1836 and 1837.