In this thesis I argue for consideration of an anticipatory level of sensemaking that influences how individuals think about and respond to organisational change. In asking how knowledgeable agents understand an altered environment, I adopt a holistic view of organisational and cognitive sensemaking literatures, to produce a sensemaking template identifying four key relational influences: Equilibration, Intentionality, Temporal Context, and Knowledge Structures. The sensemaking template is used to inform the design of an interpretive study. A single local authority in the West Midlands region of England is the setting for the field research which was working to meet increasing demands for local services against a backdrop of austerity budgets and decreasing resources in 2012-2013. I employ cognitive mapping as part of a multi-method approach to identify previously tacit frames of reference used by research participants in making sense of self-selected episodes of change in the organisation. In arguing that organisational change emerges through the enactment of cognitive agency, I use empirical data to expound on a previously invisible sensemaking process that is complex and nuanced, and which offers methodological, theoretical and analytical contributions to knowledge.