Our Course Instructors
Our instructors are seasoned procurement experts who bring real-world experience and practical insights to every course.
Marijn Overvest 
Marijn has upskilled over 200+ procurement teams from all over the world, with clients ranging from Fortune 500 companies to small businesses
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He is the founder of Procurement Tactics and a recognized expert in the field of negotiations, sustainability, and strategy building.
Marijn brings deep industry experience across procurement, FMCG (both retailers and suppliers), aviation, and pharmaceuticals.
His practical, data-driven approach has helped organizations at every scale transform their procurement processes and achieve long-term value through smart, sustainable strategies.
Ralph De Groot
With 10 years in Marketing and a focus on SEO, Growth, and Lead Gen, Ralph specialize in Generative AI and prompt engineering for tools like ChatGPT, Gemini, Claude, Perplexity, and DALL·E.
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He is also the founder of Procurement Tactics and My Codeless Website, two platforms that reflect his passion for building scalable, user-focused digital solutions.
With a strong foundation in both consulting and hands-on execution, Ralph helps businesses integrate AI tools into their workflows to improve efficiency and performance.
His ability to bridge technical innovation with marketing strategy makes him a valuable partner for teams navigating the evolving digital landscape.
Zoya Chechulina
Zoya is a senior professional with 20+ years’ experience in procurement, compliance, transformation, and leading global projects and shared service centers.
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Her expertise extends to risk management, business continuity, human rights, and corporate social responsibility.
Zoya is also highly skilled in managing shared service centers and leading international, multi-cultural projects, making her a valuable asset in global operational excellence.
Harold van Zelderen
Harold is a sourcing Manager at bol.com with 10+ years’ experience in procurement, specializing in FMCG, retail food, category management, and a background in marketing strategy and sales.
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With a strong foundation in marketing strategy and sales management, Harold brings a well-rounded perspective to procurement and sourcing.
His expertise spans FMCG, retail food, and category management, where he has consistently delivered value through data-driven decision-making and supplier collaboration.
Known for his strategic mindset and hands-on approach, Harold plays a key role in optimizing sourcing processes and driving commercial success at bol.com.
Eveline van Dam
With 10+ years in Retail and FMCG, Eveline specializes in food innovation and has helped 25+ companies—including suppliers, start-ups, retailers, and foodservice brands—develop commercially viable, consumer-focused solutions.
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Her expertise lies in bridging market trends with product development to create solutions that not only meet consumer needs but also drive commercial success.
Eveline has played a key role in guiding fresh food suppliers, start-ups, retailers, and specialty stores through the innovation process, from concept to launch.
With a deep understanding of the Retail and FMCG landscape, she brings strategic insight and hands-on support to brands aiming to stand out in competitive food markets.
Rasa Raoufi
Rasa is a co-founder of Mithra-AI Solutions with 10+ years of international experience, specializing in procurement, SaaS, and IT consulting, and proven success in driving business value through supplier management and global partnerships.
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Backed by a solid educational foundation, Rasa has over a decade of experience working with multinational and diverse stakeholders, delivering results through collaboration and strategic insight.
He brings more than three years of expertise in software implementation, IT consulting, and Software as a Service (SaaS).
As a seasoned procurement professional, Rasa excels in supplier segmentation, category management, supplier performance, and purchasing and planning, making her a key driver of operational excellence and long-term value creation.
Yme Dijkstra
Yme is a trainer, advisor, and speaker on team development and leadership with expertise in collaboration, connection, workload, well-being, and organizational growth.
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He works closely with organizations to strengthen team dynamics, improve leadership capabilities, and foster healthier, more connected work environments.
With extensive experience in both training and advisory roles, Yme supports teams in navigating challenges related to workload management, well-being, and organizational development, enabling sustainable performance and long-term growth.
Rens ter Weijde
Rens is an in-house negotiation trainer and CEO at KIMO, a former McKinsey consultant with negotiation experience across G20 politics, C-level corporates, consultancy firms, global banks, venture capital, law, and mergers & acquisitions.
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With a career rooted in high-stakes environments, Rens brings a deep understanding of complex negotiation dynamics.
From advising senior leaders at global banks to supporting deal-making in venture capital and M&A, he combines strategic insight with real-world application.
His background at McKinsey and leadership at KIMO reflect his commitment to helping individuals and organizations negotiate with confidence, clarity, and impact—whether in the boardroom, courtroom, or on the global political stage.
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Our trainers can provide teams with targeted skill-building programs that combine teamwork, accountability, and concrete deliverables to drive better deal results and assemble high-performing teams.
