March, 2026.- In a market saturated with creative promises that often overlook business goals, Courtney Tsitouris joins Greatest Common Factory (GCF) with a clear mission: to turn creativity into “growth fuel.” As the first Chief Creative Officer in the agency’s 15-year history, Tsitouris not only takes on the responsibility of honoring co-founder John Trahar’s legacy but also drives an evolution toward an agile, veteran-heavy, and deeply strategic structure. Under her leadership, GCF moves away from traditional hierarchy to operate as a “non-agency” that prioritizes impact over size. Tsitouris champions a vision where an idea’s beauty is irrelevant if it doesn’t move the conversion needle, integrating everything from CRM to ambitious brand campaigns into a single engine for results.
In this exclusive interview with Roastbrief, Courtney breaks down how GCF’s use of Artificial Intelligence—dubbed “GCF Brain”—focuses on freeing humans from administrative burdens to allow them to fall in love with the details that truly matter. With a background that combines massive conversion success with an undeniable entrepreneurial spirit, Tsitouris explains why researching until she “dreams in customer” is the only path to success. Discover how this creative leader is using her sensibility to amplify the brand truth for names like Crocs and why, in her philosophy, there is nothing “sexier” than an insurance email that successfully converts, proving that in 2026, the true magic of advertising lies in the return on investment.
Redefining the Agency as a “Growth Fuel Company”: You’re repositioning Greatest Common Factory as a “growth fuel company.” What does that term mean operationally and philosophically? How does it change the agency’s relationship with clients, the type of work you pursue, and the metrics by which you measure success?
Growth fuel means output, it’s creative with receipts. Clients have the marekting engine for growth, but the creative fuel determines how much power it generates. We’ve all been part of agencies where awards matter more than client results. That’s not how I want to run an agency.
We ask clients for results, which many creative eople don’t do because they’ve already moved on to the next thing. We need to see how commercials, social, CRM, and conversion ignite, so we can get people talking in ways that increase all the outputs.
What’s shifting our client conversations most is the notion of system check. We start by isolating the bottlenecks that are prohibiting growth. When we can define a brand truth that everyone’s missed right under their noses, we create the main ingredient for measurable growth. For example, we’re opening a new market for Crocs, kids, because we saw their (now obvious) demand for footwear that doesn’t bother them with shoelaces. That’s growth fuel.
The GCF Brain & Human AI: You’re creating a proprietary “human AI approach” called GCF Brain, employing custom versions of more than a dozen tools. How do you ensure this AI stack amplifies human creativity and strategic instinct rather than replacing it? What specific creative or strategic problems are you building it to solve that off-the-shelf tools cannot?
I’m quicker to a scope and a quote. When you’re inventing for a client and you’re applying the creativity that you put to the message and the story and the narrative, you need some tools because you’re dealing with a dynamic rather than a fixed thing.
So we’re customizng an AI model to replace things where we don’t need to be spending our time, like figuring out proposals and costs. It’ll cross-communicate so we can do those admin things faster and put all our focus on the creative and strategy that we’re supposed to be doing. We need to be free to invest the time to fall in love with all the details that matter.
We won’t be trying AI for creative. It’s great for admin, research, and even insight development because it can speed things up and take you to threads you never knew existed, which I love. But when it comes to coming up with the line or the thing or applying any type of humanness, which is what we’re doing here in appealing to humans, it is just going to fall short. If there were a magic silver bullet, we’d see it by now. It’s not happening.
Stepping Into a Legacy: You’re the first Chief Creative Officer in the agency’s 15-year history, taking over following the passing of co-founder John Trahar. How do you honor the legacy and creative foundation he built while simultaneously putting your own stamp on the agency and leading it in a new direction?
I have been through John’s underwear drawer. I’ve read almost everything he’s written. I’ve been in all of his decks, seen all his notes, browsed his computer. You know, it’s just an interesting way to know somebody.
And because I was in the process of rebranding GCF, I had to interview everyone about him. Then I went to his funeral. I stood there and listened to people talk and eulogize John’s phrase, “make things better,” which is our agency mantra.
The dumbest thing you can do is walk in and try to change the culture of a company that’s succeeded for 13 years. So that’s not my job. My job is to try to use my own sensibilities in service of John’s vision. This is how I think of it. I’ll have differences, of course, but, like, Make Things Better will always be our LLC. We’ll continue to make shirts about that.
John created a logo with a Venn diagram in it, and the concept of overlap is super important to me. It feels very synergistic and lucky in a lot of ways, because I share that mindset. Melisa, our CFO who’s been here from the beginning, keeps telling me how much I remind her of John.
The Entrepreneurial Creative Leader: You’ve founded a food and wine classic, run a publishing company, and served as an interim CEO. How does that entrepreneurial mindset shape your approach to leading creative at an agency? Do you run the creative department like a startup founder would, and if so, what does that look like day-to-day?
No, I think it’s the opposite. I think it’s that I bring the mindset of a marketer to all those things. M dad owned an agency. I only ever wanted to be one thing, a creative director, my whole life. Whenever I’ve done anything else, when I ran the Food and Wine Festival, I was the one activating sponsorships. You know, there’s marketing in the sales decks. There’s marketing in everything.
I thrive is when I understand the context around the problem. I find out what the locals are saying. I research the reviews. I know outside the brief.
George Lois once said that if you don’t love the product, you’re never going to do a good job. And I believe that. And so I need to work until I fall in love with the product every time.
From Conversion to Storytelling: Your background spans CRM programs driving up to 45% conversion improvements alongside highly creative brand work for Secret and Gillette. How do you, as a CCO, ensure that the agency’s creative storytelling is equally obsessed with measurable business outcomes? Where do those two forces converge in your process?
Well, I think everything is sexy. Everything from a headline to a big idea to an insurance email. I really can get excited about an insurance email. I really can. So when I’m talking about how to flip a subject line or what the CTA should say, or I’m talking about a big idea for Venetian, it is always about conversion.
I never, ever, ever start just with ideas. I have to do an incredible amount of research until I’m dreaming in customer. Until them, I’m not gonna start.
On weekly calls with clients I want to know how we did last week. I don’t care that it was just a little sale email. I want to know because I’m going to learn from it and we’re going to keep optimizing. At the end of the day they’re going to invite me back because we nailed the conversion or we didn’t and I don’t care how cool the idea sounded. Commerce is what’s really cool.
The Lean Team Advantage: You lead a “lean team of veterans built for speed, scale, and substance.” How do you structure workflows and client relationships to compete with much larger agencies, and what creative advantages does a lean, senior-heavy model offer that a traditional agency hierarchy cannot match?
Before COVID you didn’t want to be called a freelancer. Like, it wasn’t like a respected term because all the best people went to the agencies. And then after Covid, all the best people became freelancers.
So we’re able to keep a core team of six and expand and contract as the business needs, but we get to tap into this amazing workforce. It’s an expansive approach to resourcing. We can compete effectively with much larger agency organizations because we’re not stuck.
We’re focused on growing an agency, not building an organization. So we’re kind of the non-agency agency. We come in to help you grow, and we resist the temptation to weigh ourselves down with structure. The measure of our success isn’t size; it’s impact, what we’re achieving with clients.
