Avant-garde collectors like Costakis and Khardzhiev are leading names within a broader collector culture that flourished during the Russian Thaw, the post-Stalin epoch of the 1950s and 1960s. At the time, several collectors collected art that was either not or rarely acquired by museums, thus playing a major role in the preservation of cultural heritage that would otherwise have been largely lost. They purchased and preserved frowned-upon Avant-garde art, often under uncustomary circumstances, as well as art works that were labelled ‘formalistic’, or were considered undesirable for other reasons, such as art by former emigrants or art with a religious connotation.
Collectors such as Costakis, Chudnovsky, Shuster, Semenov and others collected Avant-garde art as part of broader collections of modernist art, which included works by post-impressionists, symbolists and early cubists. Their collections also played a major role in the rise of so-called unofficial art or nonconformist art -- firstly, because they acquired this nonconformist art, but also because they allowed contemporary artists access to their collections and thus offered access to an Avant-garde culture that was absent in museums. These collectors therefore also played a role in the connection between the Avant-garde and the culture of the non-conformists. The same goes for the unique collection of mainly post-Avant-garde art brought together by museum director and collector Igor Savitsky for the Nukus Museum of Art in Uzbekistan.
In a broader sense, this collector culture is a typical phenomenon of the period of Thaw (and later of Stagnation) with its typical atmosphere of limited liberties, an aspiring civil society, combined with ongoing political repression, and ongoing politicization of aesthetics.
The history of collecting in Soviet times, also mediated and informed the collecting practices of Western-European and American private and public collections. The history of the Russian collections of, for example, the MOMA, the Stedelijk Museum, the Ludwig Museum, the Thyssen-Bornemisza Museum, the CCA collection Montreal, Museum Sztuki Lodz, are immediately connected to the culture of Avant-garde art collecting. Beyond that, collections like those of the Zimmerli Art Museum of Soviet non-conformist art, could also be considered as they originate from the same collecting culture. 
The conference will take into consideration any paper considering this theme. The conference does not aim to introduce or present new collections that have not been documented yet. To avoid controversies about disputed collections, we will be hesitant to consider topics concerning recently discovered collections, or collections that have not yet been critically assessed in the field.