On-site catalogs structure situated knowledge by exploring rural and urban sites. As cognitive practices, they organize findings into a knowledge system that is – as Foucault observes concerning the emergence of natural history – a way of rearticulating the relationality between subjects and objects. In architecture, emergent on-site cataloging practices have been exploring the site specificity and potential value of materials found on-site. In this article, I will introduce the generative function of on-site catalogs as a more or less implicit way of establishing a new approach to rural and urban sites. I then go on, by means of an ethnographic inquiry, to describe three practices – Atelier Fanelsa, Studio SM/S, and Archibloom – employing on-site catalogs to gain a better sense of territories and to transform how we conceive of the objects they embody. I conclude by considering the relevance of on-site catalogs to the transformation of design practices and attitudes. (more)