The document discusses Standard on Quality Control (SQC) 1, which applies to all firms that perform audits, reviews, and other assurance and related services engagements. SQC 1 requires firms to establish a system of quality control with six key elements: leadership responsibilities, ethical requirements including independence, client acceptance and continuance, human resource management, engagement performance, and monitoring. It describes the policies and procedures firms must implement under each element to maintain quality in service engagements. The document also briefly outlines the peer review process where another professional evaluates a firm's quality control system and attestation work.