From an ethnomethodological perspective, this article describes social actors’ everyday and virtual stances in terms of their practices of provisional doubt and belief for the purpose of fact-establishment. Facts are iterated, reinforced, elaborated, and transformed via phenomenal practices configuring relations of equipment, interpretation, and method organized as “other” than, but relevant to, the everyday. Such practices in scientific research involve forms of suspended belief; in other areas they can instead involve forms of suspended doubt. As an illuminating example of this (...) latter class of virtual fact-establishment practices, I offer an extended analysis of the “yes; and…” principle of information-establishment used in improvisational theatre to progressively develop the content of a performance. (shrink)