This document discusses clinical trial monitoring. It defines monitoring as overseeing a clinical trial to ensure it follows the protocol, GCP standards, and regulations. The purpose is to protect subject rights and ensure compliance and data quality. Factors like the protocol complexity, site enrollment rate, and performance determine monitoring frequency. Sites are monitored regularly through visits to ensure proper conduct, documentation, and issue resolution. Monitors are trained and qualified by the sponsor to perform monitoring tasks and activities according to a plan.