About This RoleThe Associate Director, Country & Site Operations (CSO) is accountable for the direct line management, development, and operational effectiveness of CSO team members, including Clinical Country & Site Leads (CCSLs), Site Managers, and Site Feasibility team members supporting Biogen clinical trials across all phases of development and therapeutic areas, as based on business and department needs This role ensures CCSLs are appropriately deployed, coached, and equipped to deliver high-quality country and site operations, including country intelligence, investigator and site engagement, sponsor oversight, issue escalation, and cross-functional collaboration. The position promotes consistent execution, inspection readiness, sustainable workload management, and clear accountability across assigned country portfolios. The role partners closely with CSO leadership, Clinical Trial Delivery Units (CTDU), Clinical Monitoring Leads (CMLs), Site Managers, Worldwide Medical, affiliate teams, Quality, Human Resources, andCRO/FSP partners. The position may also lead selected country, site, or CSO initiatives based on portfolio and organizational needs.What You'll DoKey stakeholders include Country & Site Operations (including Clinical Monitoring, Site Feasibility and Patient Recruitment), CTDU, Clinical Development, Worldwide Medical, Affiliate Leadership, Quality, Regulatory, Human Resources, CRO/FSP partners, investigators, and research sites.Provide direct line management for assigned CCSLs, SMs, and Site Feasibility team members (as based on business and department needs), including regular 1:1s, objective setting, performance reviews, development planning, coaching, recognition, and timely management of performance or conduct concerns in partnership with Human Resources and CSO leadership.Build CCSL, Site Manager, and Site Feasibility team capability and succession strength through structured onboarding, mentoring, feedback, development assignments,