The association Sansusī was founded in 2013 by a group of enthusiasts to organize an event in the courtyard of the guest house on the second weekend of August 2014 – an alternative chamber music festival Sansusī. Since then, the festival has been held annually. The original idea was to create an open-air chamber music festival combined with the atmosphere of a small rock festival – live in a tent, but listen to classical music. Although the festival program includes many chamber music opuses of different centuries and styles, one of the main focuses is the promotion of contemporary chamber music. Starting in 2016, the festival also includes other contemporary stage art forms – circus, dance, theater plays, and performance art. Great attention is paid to the presentation of works of art, which results in their display in non-traditional places and forms. One of the greatest joys of Sansusī is the joy of experimentation, which often surprises the audience.

Since 2015, the association Sansusī has expanded beyond the usual weekend in August. Now the association is also engaged in stage work and the production of various events and recordings. During these years, more than ten new works have been commissioned, such as chamber operas, theater plays, as well as stage works for children, and interdisciplinary stage and video works. There are also collaborations with various organizations that organize city celebrations, award ceremonies, corporate events, providing them with musical programs and artists.

Since 2016, Sansusī has also hosted a variety of artist residencies, initially featuring works created specifically for the festival, but later followed by various other residency programs. One of the most important Sansusī residency programs is Sansusī Well-being Residencies, established in 2017, where artists interact with the community of Sēlija County, especially with patients and staff of Aknīste Psychoneurological Hospital, residents of the social care center, and children in the area. Since 2017, the former festival home – guest house – has been transformed into the Sansusī Residence Center in Susēja.