Change has often been said to characterise retailing, and research on retail change is extensive. However, though much of that research has focused on retail formats, it has not sufficiently addressed the fluid nature of retailing and how its formats emerge. This paper offers a more dynamic conceptualisation of retail format change by introducing the concept of retail formation. Taking a constructivist market studies approach and drawing upon an ethnographic study of a Swedish consumer electronics retailer, the paper shows how retail formations are continually being made in a dynamic process that can be initiated by various actors, does not necessarily follow a logical order, and commonly produces unexpected results. The concept of retail formation allows us to better understand the increasing fluidity of retailing enabling us to trace complex market processes, examine multiple actors simultaneously, and taking into account the socio-historical and socio-cultural dynamics involved in shaping retail markets.