Principal Systems Engineer – Defence. Requires SC Clearance to start and DV eligibility. Location - Berkshire 5 days per week. Salary – Competitive DoE. We’re supporting a leading organisation operating at the forefront of defence and secure systems engineering, looking to appoint an experienced Principal Systems Engineer to take a key leadership role across complex, high-impact programmes. This is an opportunity to work on mission-critical systems in a security-sensitive environment, providing technical leadership across the full systems lifecycle while guiding multidisciplinary engineering teams. The Role • Lead the development, integration and delivery of complex systems across the full lifecycle • Provide technical oversight and assurance, ensuring solutions meet stakeholder, safety and security requirements • Manage and mentor multidisciplinary engineering teams • Own and review requirements, architecture and technical documentation • Ensure compliance with relevant industry and engineering standards Essential Skills & Experience • Extensive experience in systems engineering across the full lifecycle • Strong working knowledge of requirements management and modelling tools (e.g. DOORS, UML, SysML, Enterprise Architect) • Proven ability to produce and review high-quality technical documentation • Demonstrable leadership and team management experience • F...