Provides onsite IT support for a dedicated client, troubleshooting hardware, software, networks, Microsoft 365, Active Directory, user accounts, printers, and mobile devices. Manages service tickets, deployments, onboarding and offboarding, vendor coordination, process documentation, escalations, KPI reporting, and client communications. Supports multiple client locations in San Diego County and participates in a 24/7 on-call rotation while maintaining service-level and customer-satisfaction standards.