Senior Security Architect

Job Description

Leonardo UK is seeking a Senior Cyber Security Architect to join our Cyber & Security Solutions Division. In this role, you will shape secure‑by‑design architectures for complex customer environments, ensuring that security principles, patterns and controls are embedded from the outset. You will translate business and mission objectives into robust, risk‑informed security architectures and produce clear, actionable artefacts that guide the safe, consistent and resilient implementation of platforms and services.

You will work in an agile, collaborative environment with a hybrid blend of home and on‑site working, maintaining close engagement with colleagues, engineering teams and customers.

• Relate - Build trusted relationships with customers, understanding their mission, constraints and operational context. Engage with stakeholders at all levels to ensure architectural decisions align with their objectives.
• Understand - Analyse complex systems and requirements, even with incomplete information, to define secure architectural options grounded in recognised security principles, patterns and frameworks.
• Assess - Apply a risk‑based approach to architecture. Identify threats, vulnerabilities and design weaknesses, and articulate these in business‑relevant language to support informed decision‑making.
• Treat - Define proportionate, layered security architectures across people, process and technology. Recommend security controls, patterns and design approaches that enable customers to meet their objectives while managing risk effectively.
• Assure - Develop and apply architectural assurance criteria. Conduct design reviews, compliance assessments and architecture governance activities to ensure solutions meet required standards and regulatory expectations.
• Develop - Contribute to Leonardo's architectural frameworks, reusable patterns and security offerings. Support business development by shaping technical solutions and providing architectural leadership in bids and proposals.

This role offers the opportunity to influence major programmes and ensure that solutions meet the highest security and architectural standards. You will work alongside a multidisciplinary team of consultants, engineers and domain specialists.

• Strong consulting and stakeholder‑engagement skills
• Ability to communicate complex architectural concepts clearly
• Adaptability, reliability and high‑quality delivery
• Collaborative mindset and willingness to support team development

• Recognised professional certifications in Cyber Security, such as Sec+, CISMP, CISSP, CCSP, SABSA, TOGAF and AWS/Azure cloud certifications.

• Deep understanding of TCP/IP, OSI layers, network protocols and associated architectural risks
• Ability to derive security requirements and architectural controls from high‑level functional or mission objectives
• Experience decomposing complex systems into modular, secure architectural components
• Ability to lead architectural work streams and influence delivery outcomes across time, cost and quality
• Strong stakeholder management, balancing technical clarity with empathy and business awareness
• Experience mentoring junior architects or consultants
• Ability to articulate the rationale for architectural security controls to both technical and non‑technical audiences
• Technical depth in network, application, cloud or system security architecture
  , including control design and threat mitigation
• Understanding of the UK MOD, defence or national security domain is beneficial

This role is subject to pre‑employment screening in line with the UK Government's Baseline Personnel Security Standard (BPSS). An additional range of Personnel Security Controls referred to as National Security Vetting (NSV) may apply, this could include meeting the eligibility requirements for The Security Check (SC) or Developed Vetting (DV). For more information and guidance please visit

At Leonardo, our people are at the heart of everything we do. We offer a comprehensive, company‑funded benefits package that supports your…