Abstract: Source data and its source documents are the foundation of clinical research. Proper source data management plays an essential role for compliance with regulatory and GCP requirements. Both paper and electronic source data co-exist in China. Due to the increasing use of electronic technology in pharmaceutical and health care industry, electronic data source becomes an upcoming trend with clear advantages. To face new opportunities and to ensure data integrity, quality and traceability from source data to regulatory submission, this document demonstrates important concepts, principles and best practices during managing source data. It includes but not limited to: ① important concepts of source data (e.g., source data originator, source data elements, source data identifier for audit trail, etc.); ② various modalities of source data collection in paper and electronic methods (e.g., paper CRF, EDC, Patient Report Outcomes/eCOA, etc.); ③ seven main principles recommended in the aspect of data collection, traceability, quality standards, access control, quality control, certified copy and security during source data management; ④ a life cycle from source data creation to obsolete is used as an example to illustrate consideration and implementation of source data management.