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We connect the economy for sustainable business. Our trusted e-procurement platform, with its integrated Mercateo Marketplace and Procurement Portal, enables effortless sourcing and purchasing for B2B and public sector organisations.

Unite Connections

We facilitate connections in bold, new ways

Alongside anonymous spot-buying and one-to-one partnerships, our platform is centred around the evolution of enduring and effective relationships, supporting business continuity and supply chain resilience.

Unite Work

Work at Unite

We want our workspaces – real and remote – to reflect our platform. That means a courageous culture where fairness, honesty, diversity and sustainability are central to all we do. And we’re always human, helping us connect and create value for others.

Unite About Adding Value

Adding value since 2000

With 20 years’ experience, we’ve got strong foundations: fair competition, trust-based partnerships and European data sovereignty. Find out more about where we’ve come from and what we’ve learned along the way.

Connecting businesses across Europe

We’re based in Leipzig, Germany, with more than 700 employees across 12 countries. Wherever we’re located, we’re united to deliver lasting change, transform B2B commerce and strengthen local economies.

Here you’ll find all the details you need to contact our local teams.

Meet our leaders

Our ever-expanding ecosystem covers buyers, suppliers, manufacturers, distributors, technology partners and trade associations – all backed up by our growing team. Find out more about our leaders here.

“The opportunity to have an impact is tremendous. For me, it’s addictive. You see how much you can improve.”

Dr Sebastian Wieser
Founder and CEO

Sebastian co-founded Unite (then Mercateo) in 2000. As CEO, he's leading our company’s strategic direction. He's our visionary, the maverick mind behind our innovative B2B network. Sebastian started his career at McKinsey & Company, advising clients on IT strategies.

Sebastian is known for his positive and passionate approach. He’s driven by finding the right solution, believing innovation is not possible without motivation. And he values our transparent and optimistic culture where issues are brought out into the open and people are galvanised to improve. “I’m proud of what is here today, and excited about what we can build in the future,” he said. “It’s not only about having the idea – it’s being able to put it in place.”

“I completely trust in the potential of people and want to help them develop and succeed.”

Peter Ledermann
Board Member and Managing Director

Peter has been on Unite’s Executive Board since 2000. Today his responsibilities stretch from finance and legal to human resources and organisational development. Pragmatic and personable, he previously worked for E.ON Energie where he was responsible for HR and sales.

Peter has been pivotal in establishing and cementing our values, and encouraging a holistic and human-centred approach to development. He thrives on a challenge and is always open to new possibilities. His warmth and optimism are felt throughout the organisation as he works to create value for our employees, shareholders, and the network. “Unite’s growth is like a village becoming a big city,” he said. “As we scale and optimise our processes, we must work hard to keep our wonderful village culture.”

“You should always be open to new experiences and challenges, being curious helps and casts out fears.”

Christel Constant
Board Member and Managing Director

Christel joined Unite’s Executive Board in 2022 and is responsible for marketing, sales and customer success. She brings more than 20 years of experience in leadership roles. At the B2B financial services platform Edenred SA, she contributed to hyper-growth, notably in the German market.

Christel is a doer with a big heart, who initiates and believes in change and likes to forge new paths. With a global mindset, she enjoys translating complex strategic issues into customer benefits and finding pragmatic solutions with fellow team members. For a successful collaboration, she values trust, honesty and appreciation. Interacting with others is especially important, and she quickly wins them over with her positive and likeable demeanour.

Christel sees Unite as a one-of-a-kind B2B commerce platform that connects dynamic market mechanisms with participants, thereby making the world more sustainable. “Encouraging diversity, equity and inclusion within the teams I work with has been important to me throughout my career. As Unite's first female executive director, I want to continue championing this cause, and create a space where everyone can contribute harmoniously.”

“Sustainability is the competition where cooperation always wins. Every day is an opportunity to understand our world better and provide solutions for the challenges ahead.”

Dr Bernd Schönwälder
Board Member and Managing Director

Executive Board member and managing director Bernd is responsible for platform, IT and operations. He joined Unite in 2010 as head of business development and held market leadership roles on the board for many years before taking on his current position in 2022.

Before joining Unite, Bernd spent a decade as the founder and managing director of a company in the financial sector, developing technology innovations for low-latency exchange trading.

With a background in engineering, information theory and psychology, Bernd's entrepreneurial focus is on the individual parts coming together to form the big picture that is Unite. He has an infectious fascination for the interplay between people and technology, providing impetus for our value discussions regarding topics like innovation and platform architecture.

“B2B performance is built on sustainable business relationships,” says Bernd. “Supply chain issues and resource scarcity are contributing to volatility. Our big task is to support changes in B2B relationships with focused market mechanisms so that scarce goods get to where they are needed the most.”