This article is an examination of the principles and the challenges being met in the collecting and preservation of the archives of French national theatres, a responsibility carried out by the archives department of the Ministry of Culture and the National Archives. In 1932, there was a transfer of the historic archives of the Opera to the National archives. After that, at the end of the 1990s, a policy for collecting theatre archives was gradually worked out, under the influence of factors such as an awareness amongst theatre directors of the heritage value of these archives, the evolution of the legal status of theatres and of archives themselves and also the interventionism of the National Archives. Benefiting from their own traditions in collecting policies and by their experience in questions of selection, the National Archives and the Ministry’s archives department were able to adapt their initiatives and their tools to collect and preserve records which are as representative as possible of the different roles of the public theatre service. Some challenges still remain, such as the collecting of so-called ‘artistic’ archives, now created in the framework of public missions, or the coordination between different heritage institutions. Other issues include the development of professional expertise and the means and approaches required for digitally-born archives or certain other specific archive types. Processes of dematerialisation mean that more than ever it is important to appoint or maintain the presence of an archives expert in national theatres, able to anticipate and organize projects for the transfer and the long term preservation of archives by the National Archives, in collaboration with the ministerial archive department.