Abstract: The purpose of clinical data and safety monitoring is to insure the safety of participants, the validity of data, and the appropriate termination of studies for which significant benefits or risks have been uncovered or when it appears that the investigation cannot be concluded successfully.All clinical trials require data and safety monitoring plans, or data and safety monitoring board as necessary.The method and degree of data and safety monitoring must be commensurate with the degree of risk involved in participation in the trial and the size and complexity of the trial.The range of monitoring includes the quality of trial execution, safety data and efficacy data, while types of monitoring include continuous and cumulative evaluating trial outcome data and interim analyses

Key words: data and safety monitoring boards, data and safety monitoring plans, quality control, interim analyses