This article seeks to examine the views held by show business unions on the issue of placing during the interwar period, which corresponds historically to the period during which their ambition to control the job market was most affirmed. The issues of placing and of job market intermediaries were at the heart of artist unions’ concerns from their very emergence onwards and the fight against art agents was always among their most ancient and recurrent priorities. Although they obtained the integration of private agencies to common law placing in 1928, unions were unable to have them banned. Indeed, all attempts to create free placing mechanisms (either public via the Agence officielle du spectacle, or union-based or associative) in the 1920s and 1930s proved to be failures. Art agents therefore remained powerful intermediaries in the job market of the interwar period. The impossible substitution of fee-paying private placing by a free public or union-based mechanism owes to the very structure of art employment – fragmented, with several employers – but also to that of the cultural production system to which it is attached. The latter is itself fragmented and centred around Paris, then spreading in the rest of France. It is furthermore important to consider the difficulties in defining qualifications and professionalism in these professional environments to understand the permanence of the private intermediary on the art job market.