Architectural artefacts are negotiated as epistemic objects, an autonomous and innovative form of knowledge capable of inaugurating and institutionalising architectural research. The backbone of this publication is a dialogue between the architect Matthias Ballestrem and the philosopher and architectural theorist Lidia Gasperoni. In a vibrant discussion, they consider the epistemic value of the architectural artefact, the role of research practices in making this knowledge explicit and accessible, and the criteria for qualifying as design-based research. Alex Arteaga, Fabrizia Berlingieri, Peter Bertram, Helga Blocksdorf, An?elka Bnin-Bninski, Marta Fernández Guardado, Joerg Fingerhut, Anke Haarmann, Rolf Hughes, Rachel Hurst, Daniel Norell, Tomas Ooms, Claus Peder Pedersen, Tim Simon-Meyer, and Philip Ursprung have added short comments and images to enrich the arguments with criticism, extensions, associations, and references. An afterword by Marcelo Stamm provides a theoretical reflection on a possible taxonomy of epistemic artefacts.