Empirical research on the knowledge dynamics of biotechnology demonstrates a dual local-global knowledge flow pattern. The sector is characterised by strong spatial concentration around nodes of excellence that are interconnected through a global network. This requires a specification of the notion of proximity as a facilitator of learning processes which emphasises its multifaceted configuration. This study highlights the significance of relational proximity within epistemic communities shaping innovation processes across multi-spatial scales. These arguments are illustrated with a database-survey on collaboration in scientific publication by 109 biotechnology firms in the Danish-Swedish life-science cluster Medicon Valley.