Network Structure and Collective Cognition The concept of the organizational field is central to organization theory. Despite its influence, the construct suffers from a lack of precise definition. Most theorists accept structuration as the core dynamic through which fields emerge (Scott, 1994) and, as a result, most definitions of organizational fields contain an element of structure or place, on one hand, and an element of collective meaning or cognition on the other. These two components of organizational fields-place and meaning-have an uncomfortable relationship with each other. Although most definitions of fields acknowledge that organizational fields are simultaneously spatial patterns of interaction of participants and their common meaning systems, there is no clear understanding of how a shared network structure can lead to collective cognition. As a result, most empirical applications of organizational fields tend to emphasize one element (structure or cognition) over the other. We seek to address this issue by introducing time, history and, most importantly, memory as the bridging mechanism that connects the structural and cognitive elements of organizational fields. We observe that institutional theorists have traditionally adopted the metaphor of fields as either geographical or symbolic structures, but largely neglected the understanding that fields are also temporal structures. As Barley and Tolbert (1997, p. 99) have argued, institutions are "historical accretions of past practices and understandings that set conditions on actions" as they "gradually acquire the moral and ontological status of taken-for-granted facts" (emphasis added). We apply this insight to the construct of fields, arguing that fields are