Purpose – Provide insight into the determinants or constructs that enable informally networked supply chains to operate in order to achieve improved operational performance. Design/methodology/approach – The research is based on a wide literature review, focused on the identification of dimensions of informal networking in supply chains along network connectivity, supply chain relationship alignment, informally networked supply chain, and operational performance. These determinants or constructs of informal networking were statistically validated for validity and reliability, using a sample of 231 supply chain professionals. Findings – Four determinant of informal networking were derived: capability connectivity, describing the ability of supply chain partners to rapidly and informally integrate capabilities to service an ad hoc market requirement; relationship alignment or the ability to informally integrate resources across supply chain partners in the context of highly dynamic market situations; the informally networked supply chain itself, measuring the ability of supply chain partners to respond to transient opportunities in the context of highly dynamic markets; and finally operational performance which measures the effect informal networking has on company performance. Research limitations/implications – Future research may investigate the effects of informally networked supply chains on a broader array of measures of company performance, and additional measures of operational performance. Practical implications – These newly developed constructs or determinants give managers further insight into which dimensions need to be fostered to enable informally networked supply chains to operate, and what operational gains may be potentially realised as a result of informal networking. Originality/value – This paper contributes to enhancing the understanding of the newly emerging phenomenon of informal networking in supply chains and how it may yield operational efficiency and effectiveness gains.