Founded in 1989 and headquartered in Reston, Virginia, SOSi is a private defense and government solutions business specializing in advanced technology systems and mission support. Its capabilities include data science, software development, network engineering, intelligence, surveillance, and reconnaissance (ISR), and logistics.
Job DescriptionOverview
SOS International LLC (SOSi) is seeking a Senior Program Security Specialist to support security planning, execution, and oversight for sensitive national security programs and advanced technology efforts. The position provides senior security advice to government leadership, develops security architecture and policy, supports risk management and program protection, and coordinates with operational, technical, and interagency stakeholders. The successful candidate will bring deep Department of Defense security experience and the judgment to protect sensitive work while enabling rapid prototyping, experimentation, and transition.
Essential Job Duties
- Provide security support for the development, planning, execution, and oversight of sensitive special-handling programs and advanced technology projects.
- Provide security-related systems engineering and technical guidance and develop security architecture for mission, payload, and technology efforts.
- Develop and maintain security policies, processes, procedures, and documentation consistent with applicable NISPOM, Intelligence Community, and Department of Defense requirements.
- Prepare risk management assessments, Program Protection Plan inputs, Security Classification Guide inputs, and other security products as required.
- Maintain witting lists and support access, indoctrination, and debriefing activities for personnel approved by the cognizant security authority.
- Advise government leadership on security execution, performance, compliance, and risk; participate in meetings and brief senior officials on security matters.
- Coordinate security matters with warfighters, Combatant Commands, interagency partners, and other authorized stakeholders.
- Use secure integrated cloud environments to run common access reports and manage controlled folder structures and permissions.
- Support security-related reviews of advanced technologies, technical documentation, test plans, demonstration plans, procedures, and reports.
- Organize security meetings, maintain action-item status, and provide timely written and verbal updates to government and contractor leadership.
Minimum Qualifications
- Active TS/SCI security clearance with a current CI polygraph.
- 15+ years of Department of Defense security experience, including substantial experience supporting sensitive or special-access programs.
- Demonstrated experience with security management, security architecture, risk assessments, Program Protection Plans, Security Classification Guides, witting lists, and access-control processes.
- Working knowledge of NISPOM, applicable Intelligence Community directives, and Department of Defense security policies and procedures.
- Experience advising senior government leaders and briefing security risks, compliance matters, and recommended courses of action.
- Experience supporting secure cloud access reporting, controlled file structures, and permission management.
- Strong written, verbal, organizational, and interpersonal skills, with the ability to manage sensitive information and competing priorities.
- Ability to work full-time onsite in Arlington, VA and travel as mission requirements dictate.
Preferred Qualifications
- Knowledge of space, counterspace, and related space working groups.
- Familiarity with space policy and security efforts, including experience integrating sensors into space platforms.
- Strategic planning experience, including pre-decisional strategic analysis, policy insight, and executive-level recommendations on Department of Defense policy and strategy related to modernization, prototyping, and innovation.
- Experience supporting systems engineering, advanced technology prototyping, research and development, testing, demonstrations, or rapid transition efforts.
- Experience coordinating security requirements across multiple government agencies, operational commands, technical teams, and industry partners.
Work Environment
- Full-time onsite work in Arlington, VA.
- Work is performed in secure government and contractor facilities and requires strict handling of classified and sensitive information.
- Travel to government, partner, and operational locations may be required.
Working at SOSi
All interested individuals will receive consideration and will not be discriminated against for any reason.
Skills Required
- Active TS/SCI security clearance with a current CI polygraph
- 15+ years of Department of Defense security experience
- Experience supporting sensitive or special-access programs
- Experience with security management, security architecture, risk assessments, Program Protection Plans, Security Classification Guides, witting lists, and access-control processes
- Working knowledge of NISPOM, Intelligence Community directives, and Department of Defense security policies and procedures
- Experience advising senior government leaders and briefing security risks, compliance matters, and recommended actions
- Experience with secure cloud access reporting, controlled file structures, and permission management
- Strong written, verbal, organizational, and interpersonal skills
- Ability to manage sensitive information and competing priorities
- Ability to work full-time onsite in Arlington, Virginia
- Ability to travel as mission requirements dictate
- Knowledge of space, counterspace, and related space working groups
- Familiarity with space policy, security efforts, and integrating sensors into space platforms
- Strategic planning experience involving DoD modernization, prototyping, and innovation policy and strategy
- Experience supporting systems engineering, advanced technology prototyping, research and development, testing, demonstrations, or rapid transition efforts
- Experience coordinating security requirements across government agencies, operational commands, technical teams, and industry partners
SOSi Compensation & Benefits Highlights
The following summarizes recurring compensation and benefits themes identified from responses generated by popular LLMs to common candidate questions about SOSi and has not been reviewed or approved by SOSi.
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Healthcare Strength — Health coverage is considered a relative strength, with international plan options and substantial employer contribution that support OCONUS and travel-heavy work. Company materials also highlight a comprehensive medical offering alongside wellness support.
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Retirement Support — A 401(k) program is available, with indications of employer matching though specifics are not publicly detailed. This suggests foundational retirement support for eligible employees.
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Career-Linked Recognition & Rewards — Compensation is often characterized as competitive for cleared, hard‑to‑hire, and certain overseas or mission‑critical roles. Pay levels appear closely tied to contract demands, clearance, and location.
SOSi Insights
What We Do
SOSi is a technology and services integrator focused on the aerospace, defense, and government services industry, described as one of the largest private, founder-owned companies in its sector.







