Providing workers with rights to take strike and other forms of industrial action is an issue of fundamental concern for trade unionists and everyone involved in industrial relations. Naturally, debate focuses on what rights trade unions and their members should have and what limits (if any) should be imposed. The form in which such rights are provided is seen often, at most, as a matter of secondary importance. In Britain, workers have not been given positive rights to strike. Instead, legislation has provided unions and their members with immunities from the legal liabilities which the organisation of industrial action involves, as a result of developments in the law as made by the judges. The history of the system of immunities is examined, and it is contended that there are practical and, in particular, ideological advantages to trade unionists in adopting a system of positive rights.