Few people have been as significant to Fidelio as Katarina Martinson, the firm’s founding investor. In this interview, she shares her perspective on the firm’s long term value creation, entrepreneurial spirit, and guiding principles that continue to set Fidelio apart in the investment world.

You’ve been with Fidelio since the very beginning. Could you tell us about your time and your relationship with the firm?

It all started in 2009 when Gabriel Fitzgerald and I began discussing the concept. At the time, I had just returned to Sweden from New York, and Gabriel was working at Nordic Capital. We had known each other since our time at the Stockholm School of Economics, and our paths crossed at the perfect moment.

We combined our experiences — Gabriel’s background in private equity and my perspective on family office investments — to shape what Fidelio would become. From the start, the idea was to create something flexible and long-term, a firm that didn’t rigidly follow portfolio theories or short-term strategies but instead focused on creating real value for both investors and entrepreneurs.

In 2010, we officially launched Fidelio, and after building a solid foundation, we brought in other families as investors in 2018, while maintaining the firm’s strong foundation and flexibility that has defined us from the start. Today, Fidelio is investing out of a EUR 1bn mandate (fund III), with a growing team and a shared commitment to the founding principles.

As you mention, Fidelio has grown significantly since its early days. What do you think has enabled that growth?

I believe Fidelio’s success is rooted in its entrepreneurial spirit and culture. From the beginning, the team has approached things differently. Instead of simply following traditional private equity models, Fidelio focuses on building meaningful relationships and staying flexible to adapt to different situations. Many firms claim to be long-term, but few actually deliver on that promise.

A big part of this is the culture which values long-term thinking, collaboration, and what I would call a “doer” mentality. It’s entrepreneurial, collaborative, and, most importantly, grounded in a humble approach. Whether you’re a partner, an investor, or a member of the team, the focus is always on doing what’s best for the companies. There’s no room for prestige or unnecessary hierarchy — it’s about rolling up your sleeves and building something meaningful together. I believe that’s what resonates with entrepreneurs and partners.

Another key factor is credibility. At that start - when Fidelio didn’t have a track record of its own - initial trust had to come from elsewhere, like my backing. The team soon delivered on great investments and over time, credibility has become one of Fidelio’s greatest strengths.

Looking back, what has surprised you most about Fidelio’s journey?

When we started, I didn’t imagine Fidelio would grow to the scale it has today. My original vision wasn’t about building a large firm with multiple funds and external investors, that ambition came more from Gabriel.

What has impressed me most is how well this approach has worked. Fidelio has carved out a niche by focusing on smaller, underdeveloped opportunities that larger firms often overlook. By building from the ground up, Fidelio has created platforms that have attracted interest from bigger players. It’s been incredibly rewarding to see the success of the investments and the impact Fidelio has been able to have.

Looking ahead, what are your hopes for Fidelio’s future?

My hope is that Fidelio continues to stay true to its roots while embracing new opportunities. It’s not just about growth for growth’s sake — it’s about making meaningful investments that align with the values and culture.

I also think it’s important to maintain the sense of fun and camaraderie that has defined Fidelio from the beginning. Work is hard, but when you genuinely enjoy being with your colleagues and feel connected to a shared purpose, it makes all the difference.

Looking ahead, I can imagine Fidelio expanding its geographical reach. But no matter how much the company grows, I believe the core of what makes Fidelio special — the long-term mindset, flexibility, and entrepreneurial spirit — will remain the same.