Accountable for the clinical and scientific content of the Clinical Study Report (CSR, including the benefit–risk narrative and patient narratives), the Investigator’s Brochure (IB, including reference safety information), the Development Safety Update Report (DSUR), and Investigational New Drug (IND) annual reports, working with Medical Writing, Biometrics, Regulatory Affairs, and Drug Safety & Pharmacovigilance. Where the CDL owns the Clinical Development Plan, the program strategy, and program-level accountability for execution, budget, and timelines, the Medical Director owns the scientific and clinical content of the protocol, the medical monitoring of the program’s clinical trials, and the medical integrity of the clinical data and documents that flow from them.