Routine quality evaluation is providing evidence of significant variations in key indicators of quality between services, and also between individual practitioners. This paper offers reflections, primarily from a service management perspective, on the process and implications of introducing a standardized system for quality and outcome measurement (CORE) into psychological therapy services. In the context of a predominant framework of external, non-managerial supervision of clinical work, the role of the service manager in ensuring competent, safe and accountable practice is discussed and potential tensions identified. The stages of implementation, together with attendant challenges and pitfalls, are outlined as part of a process of organizational change. The critical importance of winning practitioners' 'hearts and minds' and also ensuring data completeness and quality are highlighted as essential pre-requisites for ensuring practitioner commitment and subsequent utility of outcome measurement data.