Senior Quantity Surveyor / Commercial Manager Location: London SE1 Sector: Defence | Modular Construction Employer: Leading Main Contractor A leading UK main contractor with a strong and growing Defence Division is seeking an experienced Senior Quantity Surveyor or Commercial Manager to join their team based in London SE1. The business is recognised for its expertise in modular and off-site construction, delivering complex, secure and high-quality projects for defence and government clients across the UK. The Role You will take commercial responsibility for high-value modular defence projects from pre-construction through to final account, working closely with operational, design and supply-chain teams. Key responsibilities include: * Full commercial management of defence projects * Cost planning, procurement and subcontract management * Contract administration (NEC / JCT experience preferred) * Risk and opportunity management * Change control, valuations and final accounts * Supporting and mentoring junior commercial staff * Liaising with clients and key stakeholders in a secure environment About You * Proven experience as a Senior Quantity Surveyor or Commercial Manager within a main contractor * Strong background in defence, infrastructure, or secure/government projects * Experience with modular, MMC or off-site construction is highly desirable * Excellent commercial and contractual knowledge * Ability to manage complex projects and lead commercially with confidence * Eligible for or already holding appropriate security clearance (or willing to obtain) What’s on Offer * Competitive salary and comprehensive benefits package * Long-term career progression within a growing defence division * Opportunity to work on innovative modular construction projects * Stable workload and strong project pipeline * Central London (SE1) location with flexible working options If you are a commercially driven professional looking to play a key role in delivering secure, cutting-edge modular defence projects, we’d like to hear from you