In this paper we establish a dialogue with Living with Buildings, an exhibition organised by the Wellcome Trust, to contextualise NOTBAD (Niches for Organic Territories in Bio-Augmented Design), a multidisciplinary research project at the intersection of architecture and microbiology, sited within a wider historical discourse connecting architecture and health. We extend the historical analysis to suggest that architecture finds itself at a crossroads. Although there is a growing understanding of how much architecture influences our wellbeing, architectural thought still clings to the antibiotic turn. Following the tradition of exchange between architecture and medicine, we propose the notion of Probiotic Architecture as a way of framing the shifting understanding of health in architectural design, suggesting that the microorganisms that colonise humans (the human microbiome) and our built environment (the built environment microbiome) have the potential to influence our health and the resilience of our buildings. Against the backdrop of the design research project Niches for Organic Territories in Bio-Augmented Design (NOTBAD), we suggest the need to reverse notions that all microbes are bad, to and propose instead materials and prototypes that encourage benign microbial growth

© The Author(s), 2020. Published by Cambridge University Press