Abstract
This chapter explores the concept of market infrastructure, which is tentatively defined as a materially heterogeneous arrangement that silently supports and structures the consummation of market exchanges. Specifically, the authors investigate the enactment of market infrastructure in the US grocery retail sector by exploring how barcodes and related devices contributed to modify its market infrastructure during the period 1967–2010. Combining this empirical case with insights from previous research, the authors propose that market infrastructures are relational, available for use, modular, actively maintained, interdependent, commercial, emergent and political. The authors argue that this conception of market infrastructure provides a powerful tool for unveiling the complex agencements and engineering efforts that underpin seemingly superficial, individual and isolated market exchanges.