This digital collection of over 2,700 negatives, prints, slides, and transparencies by Swiss photographer Balthasar Burkhard (1944–2010) chronicles the 1972 exhibition documenta 5: Questioning reality—Image worlds today.

Organized by curator Harald Szeemann (1933–2005) with support from a sizable team of collaborators, documenta 5: Questioning reality—Image worlds today took place at the Neue Galerie and Museum Fridericianum in Kassel, Germany, from June 30 to October 8, 1972. The event was arranged into thematic shows that focused not only on contemporary art but also on advertising, science fiction, outsider art, urban planning, and other visual realms. The sections devoted to contemporary art featured vast surveys of current movements, such as photorealism, conceptualism, body art, and postminimalism. More than 150 artists participated; among them were Vito Acconci, Michael Asher, John Baldessari, Dan Graham, Joan Jonas, Agnes Martin, Yoko Ono, and Ed Ruscha.

This digital collection forms part of the Harald Szeemann Archive and Library.