In many countries governments and labor unions have contested the post-war rise of temporary agency work, arguing that this innovation infringed on workers’ rights and security. We investigate the rhetorical strategies used by Dutch temporary work agencies (TWAs) to gain legitimacy for their business between 1961 and 1996. Our conclusion is that the TWAs’ trade association ABU developed a sophisticated rhetoric of “self-restraint” to legitimize the deployment of a non-standard labor arrangement. The core message was that – if applied properly - agency work did not threaten permanent employment. The complexity of the inclusive nature of this rhetorical approach, aiming to acknowledge the concerns of multiple stakeholders, was reflected in ABU's difficulty in aligning its claims of socially responsible behavior with an effective defense of the sector's economic interests. Still, the consistent focus on restraint lent credibility to the claimed function of “allocating” workers to their jobs that eventually gained the TWA industry fundamental acceptance as a responsible labor market actor.