Manager M365 Administrator Jobs in Reston, VA (NOW HIRING)

Three Saints Bay, LLC. a government contracting industry leader, is seeking an experienced 365 Admin and Help Desk Manager to lead our IT operations with a strong focus on Microsoft 365 cloud ecosystem, endpoint management, security operations, and compliance with CMMC (Cybersecurity Maturity Model Certification) and NIST SP 800-171 requirements. This is a hybrid position reporting into either our Manassas, VA office or our Charleston, SC office. The ideal candidate will oversee the administration and optimization of Microsoft Cloud tools while managing a help desk team to deliver efficient end-user support and troubleshooting. This role combines strategic leadership, technical expertise in Microsoft security and productivity solutions, and hands-on involvement in compliance and incident response for a secure, efficient IT environment (particularly suitable for organizations handling Controlled Unclassified Information (CUI) or working with DoD/federal requirements). Key Responsibilities * Lead the administration, configuration, and optimization of Microsoft 365 (M365) environments, including Exchange Online, Teams, OneDrive, SharePoint Online, and related services. * Manage Microsoft Intune (Endpoint Manager) for device enrollment, compliance policies, configuration profiles, application deployment, Autopilot provisioning, security baselines, and endpoint security across Windows, iOS, Android, and macOS devices. * Oversee Microsoft Defender (including Defender for Endpoint, Defender for Office 365, Defender for Identity) for threat protection, vulnerability management, and incident response. * Administer Microsoft Sentinel for security information and event management (SIEM), threat hunting, analytics, and automated response workflows. * Ensure the organization's IT systems and processes comply with NIST SP 800-171 controls and CMMC Level 2 (or higher) requirements, including policy development, control implementation, gap analysis, audit preparation, System Security Plan (SSP) maintenance, and Plan of Action & Milestones (POA&M) tracking. * Manage and mentor the help desk/support team, including staffing, training, performance management, shift scheduling, and escalation processes. * Provide advanced troubleshooting and resolution for end-user issues related to M365 applications, device management, security alerts, access problems, and general IT incidents. * Develop and enforce IT policies, procedures, and best practices aligned with zero-trust principles, conditional access, multi-factor authentication (MFA), data loss prevention (DLP), and compliance frameworks. * Monitor system performance, security posture, and compliance metrics; generate reports for leadership and auditors. Required Qualifications * Bachelor's degree in Information Technology, Computer Science, Cybersecurity, or a related field (or equivalent experience). * 7+ years of progressive IT experience, including 4+ years in a managerial or supervisory role. * 5+ years of hands-on expertise administering Microsoft 365 environments (E3/E5 preferred), with deep proficiency in: * SharePoint Online (site management, permissions, governance). * Intune (device management, compliance, Autopilot). * Microsoft Defender suite. * Microsoft Sentinel (SIEM/SOAR capabilities). * Proven experience implementing and maintaining compliance with NIST SP 800-171 and CMMC frameworks (e.g., control mapping, self-assessments, remediation, or certification preparation). * Strong background in managing a help desk or service desk team, including ticketing systems, SLAs, end-user troubleshooting, and customer service excellence. * Experience with Microsoft Entra ID (Azure AD), conditional access policies, identity governance, and security baselines. Preferred Qualifications * Relevant certifications such as: * Microsoft Certified: Azure Administrator Associate, Microsoft 365 Security Administrator, or equivalent. * Microsoft Certified: Endpoint Administrator Associate. * Certified Information Systems Security Professional (CISSP), CMMC Registered Practitioner (RP), or similar. * Experience in regulated environments (e.g., DoD contractors, federal contractors, defense industrial base). * Familiarity with Microsoft Purview, Power Automate, or Power BI for reporting/compliance. * Knowledge of hybrid environments, Azure Government/GCC High (if applicable). Hiring Range: $100,000- $120,000 VEVRAA Federal Contractor Three Saints Bay, LLC and its subsidiaries offer a team-oriented working environment and the opportunity to work with exceptional, dedicated industry professionals. We offer our employees a comprehensive benefits package and the opportunity to take part in exciting projects with government and commercial clients, both domestic and international. We are an Equal Opportunity Employer. We invite resumes from all interested parties without regard to race, color, sex, sexual preference, religion, creed, national origin, age, genetic information, marital or veteran status, disability, or any other category protected by federal, state, or local law.