The paper analyses the role of external knowledge flows in the upgrading of the biomedical district of Mirandola, Emilia-Romagna region, in Italy. The district produces two types of products, namely disposables and electromedical machines, and the paper considers this second production type. The Mirandola district has been able to maintain a relatively good competitive position. The paper shows that while all firms in this sector in this region tend to have fairly good performance in terms of size and revenue growth, a significant difference exists in terms of innovation performance. Firms in the Mirandola district produce more patents and more scientific publications. From a methodological point of view, negative binomial regressions are made on the determinants of patenting and publishing activity by firms. Two major factors seem to explain the superior performance in terms of innovation. First, the significant role of the leader firms in the district. Second, linkages external to the district, namely relationships with research centres (universities in particular) located not only in the region but also in the rest of the country and abroad. The importance of external relations and institutional diversity (in terms of variety of institutions collaborating in scientific publications), appear to grow over time.