Chief Security Architect in London

Location: Central London, Greater London – United Kingdom

Type: Permanent

Salary: Up to 110,000 + senior consultancy/leadership package

Clearance: Active DV clearance essential

Sector: Defence, Government, National Security & Critical National Infrastructure

The Opportunity

We are looking for an exceptional Chief Security Architect / NCSC Head Consultant to take senior technical ownership of Security Architecture across a high-assurance cyber security consultancy. This is a senior, client-facing architecture role where you will act as a technical authority for security architecture, leading complex engagements across Defence, Government, Critical National Infrastructure and other highly regulated environments.

You will be responsible for the technical quality, governance and delivery of high-assurance Security Architecture engagements, working closely with senior leadership and operating as the accountable technical lead for an NCSC-assured Security Architecture capability. This is an opportunity for an experienced Security Architect who wants to operate at the highest level of technical leadership, influencing major programmes and helping shape the future direction of a specialist security architecture practice.

What You'll Be Doing

• Lead the design and assurance of secure architectures across complex Defence, Government, CNI and mission-critical environments.
• Define security requirements, threat models, architectural principles and proportionate security controls across the system lifecycle.
• Identify and manage security risks across high-level and detailed solution designs, providing practical mitigation strategies for new and legacy environments.
• Lead client architecture reviews, design authorities and technical workshops with senior security, technology and programme stakeholders.
• Translate complex technical risks into clear, decision-ready recommendations for CISOs, SROs, boards and programme leadership.
• Produce high-quality security architecture artefacts, including architecture documentation, risk assessments, design reviews, security requirements and remediation roadmaps.
• Set technical standards and assure the quality of security architecture deliverables produced by consultants.
• Develop security architecture methodologies, capability and best practice across the wider practice.
• Act as the senior technical point of contact for the NCSC Security Architecture offering, providing technical leadership across consultants and client engagements.
• Support business development through bids, proposals, client meetings and the development of new security architecture services.

What We're Looking For

You will be an established Security Architecture professional with significant experience operating within Defence, Government, National Security, CNI or other high-assurance environments.

You should have:

• 10+ years' experience in security architecture or closely related disciplines.
• Chartered Cyber Security Professional (ChCSP) accreditation in Secure System Architecture and Design – essential.
• Active DV clearance and the ability to meet UK residency requirements.
• Proven experience leading secure solution architecture across complex, multi-supplier and/or classified programmes.
• Strong knowledge of NCSC guidance, Secure by Design, Cyber Assessment Framework (CAF), NIST and ISO 27001.
• Experience applying risk-driven security architecture methodologies to complex systems and environments.
• Strong understanding of security requirements, threat modelling, risk assessment and security controls.
• The ability to communicate complex technical risks and recommendations to both technical and C-level audiences.
• Experience leading or mentoring security consultants and assuring technical outputs.
• Excellent client-facing, communication and influencing skills.

Desirable Experience

The following would be highly advantageous:

• Existing experience as an NCSC ACSC Head Consultant, Technical Lead or equivalent accountable lead for an assured security architecture capability.
• NCSC Certified Cyber Professional (CCP) credentials.
• CISSP-ISSAP, SABSA, TOGAF, CISM or relevant engineering chartership.
• Security architecture experience across:
• Cloud Security
• Identity & Access Management
• Zero Trust
• DevSecOps
• Secure System Integration
• Enterprise Architecture
• Digital Transformation
• Experience working on nationally significant, high-assurance or classified programmes.
• Experience developing security architecture practices, methodologies or reusable consulting assets.

Why This Role?

This is not simply a Security Architect position. It is an opportunity to become a senior technical authority within a specialist high-assurance security environment, working on complex programmes where security architecture has genuine national and organisational impact.

You'll have the opportunity to:

• Influence the architecture of complex Defence, Government and CNI systems.
• Operate directly with senior technical and programme stakeholders.
• Lead and develop other security architecture professionals.
• Shape security architecture standards, methodologies and capabilities.
• Contribute to bids, propositions and the growth of a specialist security practice.
• Work at the forefront of NCSC-aligned security architecture within high-assurance environments.

If you're an experienced Security Architect with active DV clearance and ChCSP accreditation, and you're ready to take genuine technical ownership of an NCSC-assured Security Architecture capability, we'd be keen to hear from you.