This research investigates a relevant gap in the academic literature on enterprise policy—namely, the nature of discretion and the causes that permit it during policy implementation. We found in our case studies that the programme workers who deliver policies exerted considerable discretion. Further evidence suggests that the main influences on what we call informal discretion—discretion clearly outside programme objectives—include the design of programme evaluation and audit as well as the influence of evaluators and auditors in these processes. We also found evidence of formal discretion—discretion allowed within programme objectives—through broad and ambiguous policies and procedures. Our findings and theoretical framework illustrate how discretion cannot be so easily curtailed by the market logics and strict rules of the new public management practice. Instead, we conclude that the possibility of reframing policy statements and evaluation as a learning process, from programme successes and failures, would transform our approach to policy implementation. This would require a number of institutional and incentive changes for policy actors and the public.