Senior System Administrator (Windows)Location: McLean, VA (transitioning to Chantilly, VA) Clearance Required: Active TS/SCI with CI Polygraph Salary Range: $185,000 – $265,000 Travel: Up to 20%OverviewWe are seeking a highly skilled Senior System Administrator to join a dynamic infrastructure team supporting next-generation technologies, including initiatives in the Artificial Intelligence (AI) space. This role is ideal for a hands-on technical expert who thrives in complex environments and is passionate about building, maintaining, and optimizing enterprise systems.Key ResponsibilitiesDesign, implement, and maintain Windows-based systems, networks, and applicationsArchitect and support enterprise-level Windows infrastructureAdminister and manage:Active DirectoryGroup PolicyDNSFile serversExchange / enterprise email systemsManage patching, updates, and system performance optimizationMonitor systems, troubleshoot issues, and ensure high availabilitySupport system deployments using tools such as SCCM or MDTDevelop and maintain technical documentation and standard operating proceduresProvide Tier II/III technical support via phone, email, and in-personCollaborate with cross-functional IT teams to integrate new technologiesTravel up to 20% for on-site support, installations, and maintenance