Constructivist theorists view norms as shared understandings that reflect ‘legitimate social purpose’. Because the focus is on the ideational building blocks that undergird a community’s shared understandings, rather than material forces, persuasive communication is considered fundamentally important to norm-building. In practice, this means that frames are crafted by norm entrepreneurs so as to resonate with audiences. However, the constructivist empirical literature illustrates the central importance of material levers in achieving normative change. Those who promote specific norms also manipulate frames strategically to achieve their ends and do not necessarily convince others to alter their preferences. The global debate over ‘core labor standards’ is highlighted to illustrate the various means by which frames can be distorted by communicators acting strategically, perhaps even to secure their own instrumental interests or to maintain their powerful status. Norms that do not reflect a genuinely voluntary consensus can be seen as illegitimate.