The article uncovers the complex process of educational policy enactment and the impact this process has on teachers as policy actors as they undertake the task of introducing a new mathematics curriculum in a Canadian secondary school. The three year study based on in-depth qualitative interviews adopts a classic grounded theory approach of concurrent iterative cycles of data collection, conceptual categorisation and analytical abstraction, to identify six emergent concepts indicative of policy actor engagement with the policy process: (1) Professional and Emotional Investment; (2) Decisional Legitimacy; (3) Hierarchical Trust; (4) System Integrity and Viability; (5) De-professionalisation; and (6) Identity Safeguarding. Further, and significantly, the grounded theory analysis identifies the core concept of "Affective Disruption," conceived as an interruption to an individual's emotional equilibrium resulting from interference to their cognitive sense-making in relation to policy. It is proposed these six emergent concepts and "Affective Disruption" as a core concept are precipitated within policy actors in response to the tensions created by the process of policy enactment; the research findings moving towards what might be tentatively termed a policy social psychology.