Building trust with Contextual AI: inside December19’s media strategy

We sat down with Sam Griffith, Head of Digital at independent media agency December19, to explore how their partnership with illuma is supporting their client goals.

To kick things off, can you tell us a bit about your role and about December19 as an agency?

Sam: I’m Sam Griffith, Head of Digital at December19. I lead our digital strategy and ensure we’re delivering transparent, accountable digital media solutions that drive results for our clients.

We’re an independent media agency that tries to redefine industry convention. Instead of following the traditional playbook, we give brands complete clarity and control over their media investment. Transparency isn’t just what we offer – it’s our superpower.

What makes your approach to media strategy or campaign planning stand out?

Sam: Our approach starts with original thinking rather than inherited wisdom. Where some agencies might present black-box solutions, we open everything up. Every decision, every cost, every performance metric is completely visible to our clients.

We’re free from legacy trading deals, so our recommendations are genuinely neutral and based purely on what will drive the best outcomes. This transparency extends through our entire tech stack and methodology.

It sounds like transparency plays a large role in how you work with stakeholders. How did that influence your decision to work with illuma, or shape the way you use our contextual technology?

Sam: When evaluating partners like illuma, we look for technology that enhances rather than obscures our decision-making process.

illuma’s contextual AI aligns perfectly with our philosophy because it provides clear, explainable insights about where and why we should place media. We can show clients exactly how contextual signals are informing our strategy, rather than asking them to trust a black box algorithm.

What role does AI play in your programmatic strategies today, and how does illuma’s contextual AI fit in?

Sam: We focus on AI that enhances human decision-making rather than replacing it – tools that provide clearer insights, not more complexity.

illuma’s contextual AI fits our approach because it helps us move beyond basic demographic targeting to understand the actual context where our messages will be seen. This means we can be more strategic about moment-to-moment placement decisions while maintaining full visibility into the reasoning behind each choice. It is a privacy first approach to scale reach and performance without cookies and so complements cookie-based look-alikes for net new reach. Placing ads adjacent to relevant content in moments that correlate with attention and engagement can really help drive performance!

What kinds of advertising challenges are your clients typically facing, particularly in B2B?

Sam: B2B clients are dealing with longer sales cycles, more complex decision-making, and increasing pressure to demonstrate clear ROI. Many come to us frustrated by a lack of clarity about where their budget is going or why certain channels are being prioritised.

The market dynamics make this worse. Only 5% of business audiences are in-market at any time, yet most B2B marketing still focuses on immediate activation rather than long-term brand building. That’s why we invest in econometric modelling – it gives B2B clients confidence that brand investment is as trackable as performance marketing.

The other major issue is the false economy of “playing it safe.” Being dull isn’t safe, it costs. When everyone in your category sounds the same, you’re making your brand invisible.

Can you share some outcomes or success stories from the campaigns we have worked on together?

Sam: We started working with illuma back in early 2024 and they have since grown to become a key partner of ours across a variety of different client accounts, but most notably for our client MHR, an HR, Finance and Payroll software business. As audiences become harder to engage and media becomes more fragmented, finding new contextual segments beyond our typical predefined audiences has really helped us in driving performance. CTRs are consistently higher than average and illuma Reacts’ ability to optimise live has allowed us to find those changing segments which can differ from day to day.

It sounds like reacting to real-time — and sometimes unexpected — contexts played a key role in the success of your campaigns. This is a reminder that the most effective strategy isn’t always what the client expects or wants to hear. How do you navigate that tension between pitching the right idea and aligning with client expectations?

Sam: This is where our commitment to transparency becomes crucial.

We present the evidence clearly: here’s what the context is telling us, here’s why the original approach isn’t optimal, and here’s exactly how this adjustment will improve results. Because our clients can see our complete reasoning process, they’re more willing to trust recommendations that might feel counterintuitive.

The key is never surprising clients. If we’re seeing signals that suggest a strategic shift, we flag it early and explain our thinking before taking action.

What’s next for December19? And how do your values guide your future direction?

Sam: We’re investing heavily in our people and capabilities – from our AI taskforce that’s unleashing new possibilities in media strategy, to embedding creativity deeper into our media thinking.

Our commitment to doing the right thing extends beyond client work – we’re advancing our B Corp certification driving toward Ad Net Zero compliance and fostering a culture where every person has accountability for moving the business forward. We sit on the working groups for the Alliance of Media Independents as well as the steering committee for the IPA’s new carbon calculator. We believe the future belongs to agencies that don’t just adapt to change but actively drive it.