The system review is a holistic test of a firm's compliance with quality control standards for a specific one-year period of time. Firms that perform engagements under the SASs or Government Auditing Standards, examinations under the SSAEs, or audits of non-SEC issuers performed pursuant to the standards of the PCAOB as their highest level of service have System Reviews. There are two areas of focus for the System Reviews: 1. Testing of the Quality Control System, both on the design and compliance; and 2. Engagement-Quality Control Review of the selected or "must select" engagements.