See what you’re missing. Our employees work on the world’s most advanced electronics – from detecting threats for F-35 pilots to illuminating the night for soldiers. Spanning air, land, sea, and space, we are developing the technology of tomorrow, delivered today. Drawing strength from our differences, we’re innovating for the future. And you can, too. Our flexible work environment provides you a chance to change the world without giving up your personal life. We put our customers first – exemplified by our mission: “We Protect Those Who Protect Us®.” Sound like a team you want to be a part of? Come build your career with BAE Systems.

BAE Systems is seeking a Senior Principal Systems Security Engineer to lead the integration of security engineering practices across the full systems development lifecycle (SDLC) for mission-critical DoW programs. The qualified candidate will drive the specification, design, implementation, and verification of security controls within complex system architectures, ensuring that cybersecurity and information assurance are embedded from concept through deployment and sustainment.

This role is grounded in the principles of NIST SP 800-160 (Systems Security Engineering) and emphasizes proactive security-by-design rather than reactive compliance. The Senior Principal Systems Security Engineer will serve as the technical authority for security engineering within multidisciplinary development teams, ensuring that protection strategies, threat-informed design decisions, and risk trades are woven into every phase of the engineering lifecycle.

• Lead systems security engineering activities across all phases of the SDLC, including concept definition, requirements analysis, architecture and design, implementation, integration, verification and validation, deployment, and sustainment
• Define, decompose, and allocate security requirements to system elements (hardware, software, firmware, and interfaces) ensuring traceability from threat models through verification evidence
• Develop and maintain security architectures, including protection strategies, trust boundaries, security-relevant data flows, and attack surface analyses for complex DoD systems
• Conduct and lead threat modeling, Systems-Theoretic Process Analysis for Security and adversarial analysis to inform design trades and risk acceptance decisions
• Drive the integration of security into Development Security Operations (DevSecOps) pipelines, including automated security testing, static/dynamic analysis, container security, and secure CI/CD practices
• Lead Assessment and Authorization (A&A) activities for DoD systems in accordance with the Risk Management Framework (RMF), including security control selection, implementation, assessment, and continuous monitoring
• Author and maintain security engineering artifacts including System Security Plans (SSPs), Security Concepts of Operations (CONOPS), Security Control Traceability Matrices (SCTMs), and risk assessment reports
• Evaluate and apply applicable STIGs, SRGs, and security benchmarks to system components, and develop Plan of Action and Milestones (POA&Ms) for residual risks
• Provide technical leadership and mentorship to cybersecurity engineers, systems engineers, and software developers on secure design principles and security engineering best practices
• Engage with government customers, authorizing officials, and cross-functional program teams to communicate security posture, risk decisions, and compliance status
• Support proposal development, technical volume writing, and independent review of security architectures for new business pursuits

• Master’s degree in Systems Engineering, Cybersecurity, or related field
• Active TS/SCI security clearance
• CISSP, ISSEP (Information Systems Security Engineering Professional), or equivalent certification
• Experience with Model-Based Systems Engineering (MBSE) tools (e.g., Cameo, SysML) applied to security architecture
• Familiarity with System-Theoretic Process Analysis for Security (STPA-Sec) tooling and processes
• Experience with zero trust architecture design principles and implementation
• Knowledge of cross-domain solutions, multi-level security architectures, and secure system integration patterns
• Experience supporting security engineering for embedded systems, real-time systems, or weapon system platforms
• Background in formal verification or assurance methods for high-assurance systems