Key Account Manager – Nuclear Fusion & Modular Projects

About the role

As a Key Account Manager in Assystem’s Nuclear New Build Business Unit, you will drive the growth of the Fusion and Modular Nuclear portfolio. You will build trusted relationships with strategic customers and position Assystem as a preferred delivery partner for high‑impact nuclear projects.

Key responsibilities

• Manage relationships with existing and new strategic external clients.
• Achieve sales order targets and maintain accurate CRM records.
• Provide reliable forecasting and bid tracking for high‑value opportunities.
• Develop and execute key account development plans.
• Capture strategic, high‑value opportunities and support internal BU planning.
• Identify and develop new customer opportunities.
• Represent Assystem at senior client engagements and industry events.

Required profile

• Degree in engineering, science, business or a related field.
• Proven experience in account management or business development with strategic clients.
• Track record of handling complex accounts and delivering sales targets.
• Strong communication, stakeholder management and negotiation abilities.
• Strategic and analytical mindset; ability to work autonomously and within a matrix organisation.
• Preferred experience in nuclear, energy, infrastructure or oil & gas sectors.
• Familiarity with gated bid and review processes and the fusion/modular reactor market.
• British nationality preferred due to security‑clearance requirements.

Required skills

• CRM systems
• Forecasting tools

What we offer

• Pension scheme (8% company contribution, 4% personal contribution).
• 25 days paid annual leave plus bank holidays, with the option to buy or sell days.
• Reimbursement of professional fees.
• Flexible working arrangements.
• Employee referral scheme.