Slicing through blunt theories of supply and demand, Callon presents a rigorously researched but counterintuitive model of how everyday market activity gets produced. If you’re convinced you know what a market is, think again. In his long-awaited study, French sociologist and engineer Michel Callon takes us to the heart of markets, to the unsung processes that allow innovations to become robust products and services. Markets in the Making begins with the observation that stable commercial transactions are more enigmatic, more elusive, and more involved than previously described by economic theory. Slicing through blunt theories of supply and demand, Callon presents a rigorously researched but counterintuitive model of market activity that emphasizes what people designing products or launching startups soon discover—the inherent difficulties of connecting individuals to things. Callon’s model is founded upon the notion of “singularization,” the premise that goods and services must adapt and be adapted to the local milieu of every individual whose life they enter. Person by person, thing by thing, Callon demonstrates that for ordinary economic transactions to emerge en masse, singular connections must be made. Pushing us to see markets as more than abstract interfaces where pools of anonymous buyers and sellers meet, Callon draws our attention to the exhaustively creative practices that market professionals continuously devise to entangle people and things. Markets in the Making exemplifies how prototypes, fragile curiosities that have only just been imagined, are gradually honed into predictable objects and practices. Once these are active enough to create a desired effect, yet passive enough to be transferred from one place to another without disruption, they will have successfully achieved the status of “goods” or “services.” The output of this more ample process of innovation, as redefined by Callon, is what we recognize as “the market”—commercial activity, at scale. The capstone of an influential research career at the forefront of science and technology studies, Markets in the Making coherently integrates the empirical perspective of product engineering with the values of the social sciences. After masterfully redescribing how markets are made, Callon culminates with a strong empirical argument for why markets can and should be harnessed to enact social change. His is a theory of markets that serves social critique.