Senior Sustainability Consultant

Nexio Projects is looking for a Senior Sustainability Consultant to help lead the delivery and development of our sustainability finance and reporting services. You will translate CSRD/ESRS and IFRS S1/S2 requirements into practical, audit-ready solutions for finance and sustainability leaders, build trusted relationships with senior client stakeholders, and manage engagements from scoping through delivery. This role is suited to either an experienced sustainability or ESG reporting professional with a strong technical grounding, or an audit, accounting advisory or financial reporting professional looking to apply that expertise in a hands-on, client-facing, service-building capacity.

Why this role exists 🍀

Sustainability reporting is rapidly becoming part of corporate financial reporting. CSRD and the ESRS have made sustainability disclosure a board-level, audit-grade exercise. The ISSB's IFRS S1 and S2 are becoming the global baseline while the market is increasingly demanding that sustainability strategy be translated into a credible financial business case connected to enterprise value creation and supporting capital allocation. Our clients, European mid-market companies and international groups, need advisors who speak both languages: rigorous financial reporting discipline and deep sustainability expertise. Most advisors speak one. We need both

You'll split your time between helping shape Nexio's next generation of sustainability finance and reporting services and applying them in client engagements. Rather than joining an established practice with fixed methodologies, you'll help define how we approach emerging topics such as ESRS audit grade reporting, IFRS Sustainability Disclosure (IFRS S1/S2), internal control framework, and financial decision-making for sustainability.

Client engagements will provide the testing ground for new ideas. In turn, you'll use lessons learned from delivery to strengthen our methodologies, tooling and commercial propositions, helping turn promising concepts into repeatable

Hi, we’re Nexio Projects! 🌍

Nexio Projects is a sustainability consultancy of 45+ people headquartered in Rotterdam, serving hundreds of European mid-market clients across CSRD/ESRS, EcoVadis, B Corp, CDP and net-zero strategy. We're a certified B Corp (the highest-scoring B Corp consultancy in the Benelux), a certified Great Place To Work®, top rated consulting firm per Verdantix & consultancy.nl and a Platinum EcoVadis strategic consulting partner. We practice what we advise, and we hire people who combine technical seriousness with a light touch: human, humble, hardworking, and allergic to taking themselves too seriously.

What you’ll do  🧭

Service & practice development

You'll join a team building and scaling Nexio's new services. The objective is to develop services that are commercially viable, repeatabl,e and transferable across the business – not dependent on the individual who originally created them. This will include: 

• Support the building and scaling of Nexio's reporting and assurance-readiness service lines: pre-assurance preparation, internal control and data management interoperability offerings spanning ESRS, IFRS, UK SRS, Australia AASB standards and other services which enable translating sustainability strategy into business case using financial models such as quantification of climate risk assessment, Marginal Abatement Cost Curves and Internal Carbon Pricing Develop methodologies, tooling and reusable delivery assets that make our engagements faster, more consistent and more profitable

• Build Excel-based financial models and translate operational assumptions into financial projections

• Maintain our technical positions as the regulatory landscape moves (Omnibus, ESRS revisions, ISSB amendments, UK endorsement) and turn regulatory change into a commercial opportunity

• Contribute to proposals, thought leadership and client development alongside the leadership team.

• Capturing insights from pilot engagements and using them to continuously improve methodologies, pricing and delivery approaches.

Client engagement & delivery (primarily pilot projects)

Your client work will focus particularly on new and developing service areas. You will therefore play an important role in ensuring that emerging offerings are practical, relevant and deliverable; not only technically well designed. This will include:

• Translate complex regulatory, technical and market developments into practical client solutions

• Support CFOs and finance teams in embedding sustainability into governance, planning and financial reporting processes

• Lead or support client engagements across emerging sustainability topics

• Scope projects, develop proposals and agree on clear deliverables and ways of working

• Deliver high-quality analysis, recommendations, tools and implementation support

• Design internal control frameworks, ESG data management processes and reporting manuals that make sustainability data audit-ready and act as the client's counterpart to their external assurance provider

• Adapt methodologies to the client’s sector, maturity and business context

• Coordinate multidisciplinary project teams, providing guidance and coaching to consultants throughout project delivery

What you bring 🎒

Must-haves

• 5+ years in audit, accounting advisory, financial reporting or ESG reporting/assurance: Big Four, mid-tier audit, or an in-house reporting engagement; supervise direct reports and coordinate project team reporting function.

• A professional accounting qualification (RA, ACA/ACCA, CPA or equivalent) or a Master's degree in accounting, finance, business or a related field.

• Working command of CSRD/ESRS and double materiality; strong knowledge of IFRS S1/S2.

• Experience with ESG data management, internal controls or assurance readiness.

• Experience connecting sustainability qualitative analysis with financial statements and financial decision-making

• Fluent English; Dutch or French is a strong plus.

• Proven ability to manage multiple complex, high-stakes projects and to present with authority from operational teams to the C-suite.

What sets you apart

• Experience supporting or performing limited/reasonable assurance on sustainability information.

• A track record of building or scaling a service offering, not just delivering one.

• Familiarity with ERP and ESG reporting systems (SAP, Workiva or similar).

• AI fluency: hands-on experience with agentic AI and building it into real workflows: you use it to work faster and better, not just to talk about it

• An intrapreneurial streak: you see a gap in the market or in our delivery model, and you close it.

You probably won't enjoy this if

• You want a playbook before you act. We're still writing the playbook, that's partly the job.

• You see business development as separate from consulting

• You see sustainability reporting as a marketing exercise. Our clients' reports are assured, and so is our credibility.

• You need a big-firm hierarchy to feel comfortable. We're 45 people; you'll have real ownership from week one.

• You're hoping a smaller firm means a quieter workload. In our experience, it's simply a different one: more ownership, more visibility, and clients who expect just as much. Most of us find that energising — but it's worth knowing going in.

What we offer  🎁

• A front-row seat in one of the fastest-moving areas of corporate reporting and strategy, with real ownership over how a growing consultancy responds to it.

• An annual training allowance (with time and costs partially covered) and the room to specialise.

• Pension plan, transportation allowance, wellbeing contribution, and a free Swapfiets subscription.

• Hybrid working: 3 days in our Rotterdam office, 2 days from home, with home-office equipment provided.

• A team culture that includes weekly Friday drinks with a gratitude award, bi-annual team events, and Earth Day volunteering.

• The opportunity to take ideas from early market research through to paid projects and scalable offerings

• Direct exposure to Nexio's leadership, commercial teams and senior client stakeholders

• Significant autonomy over how services are designed, tested and commercialised

Practicalities  📋

📍 Location: Rotterdam, The Netherlands (hybrid)
🕐 Type: Full-time (40 hours per week)
🗓️ Start: October 1st, 2026
📨 Applications: Reviewed on a rolling basis. If you're on the fence, apply; the worst we can say is no. Given the volume we receive, we can't send personal feedback to everyone, but we promise concrete feedback to all applicants who make it to the recruiter interview round. Our hiring process is the following:

1. Recruiter interview | online | 30 minutes: A conversation about your background, your experience, and what you're looking for in your next role.

2. Hiring manager interview | online | 45 minutes: A deeper conversation about the technical side of the role, plus a walkthrough of your take-home case study on service and proposal development.

3. Final interview | on-site in Rotterdam | 30 minutes: A chance to meet with senior members of the team, talk about how you like to work, and see if it feels like a mutual cultural fit.

4. Offer: If it's a mutual match, we'll move quickly to get you an offer. Welcome aboard, Nexian! 🎉

🌱 We are an equal-opportunity organisation and deeply value diversity, equity, and inclusion in our recruitment process. We strongly encourage applicants from all backgrounds and experiences. 🌱