During the postwar period, internal tensions plagued the Australian labour movement. Central to these tensions were the formation and policies of the Industrial Groups. While their original aim was to destroy Communist influence in unions, the Groups rapidly established themselves as a power within the Labor Party. With the goal of consolidating their position, the Groups sought to obtain legislation which would further expand their influence. In New South Wales, this legislation took the form of general compulsory unionism. The aim was to strengthen those unions with Industrial Group leadership, thereby increasing their influence at Labor Party conferences. Despite strong left-wing opposition, the legislation was introduced in November 1953. This paper traces the New South Wales legislation from the time of its enactment to its ultimate demise. The aim is twofold. Firstly, it adds to the existing body of research on the post-war history of the Australian labour movement, particularly in terms of its internal politics. Secondly, the paper aims to inform current debates by demonstrating the complex political frameworks and implications associated with union growth and security.