For years, Cannes Lions has served as the advertising industry's crystal ball.
The conversations that begin on the Croisette often influence marketing budgets, agency strategies and boardroom discussions long after the festival ends. In 2026, one topic towers above all others: artificial intelligence.
This year's Cannes Lions programme features leaders from OpenAI, Google DeepMind, Meta, Amazon, Instagram and some of the world's largest brands. AI is no longer a side conversation. It has moved to the main stage.
Yet beneath the headlines lies a more interesting story. The industry's AI debate is evolving. The question is no longer whether AI will transform marketing. The question is how.
As marketers, agencies and technology companies descend on Cannes from June 22-26, five major debates are set to dominate conversations across the Palais, beach activations and private executive meetings.
1. Agentic AI vs Generative AI
The first wave of AI adoption was centred on content generation.
Marketers experimented with AI-generated copy, images, videos and campaign assets. The focus was largely on productivity and scale.
Now the conversation is moving towards something far more ambitious: agentic AI.
Unlike traditional generative systems that respond to prompts, agentic systems can plan, coordinate and execute tasks across workflows. They are increasingly being discussed as digital collaborators rather than creative assistants.
The shift is visible across Cannes Lions.
AWS is hosting discussions around what it calls the "agentic AI future of advertising and entertainment," bringing together leaders from OpenAI, AWS and major brands to examine how intelligent systems are changing marketing operations. The theme is also emerging across enterprise technology discussions from major platform providers and consulting firms attending the festival.
The industry's central question is becoming clear:
Will AI remain a tool marketers use, or become an active participant in how marketing gets done?
2. Search vs AI Discovery
For more than two decades, digital marketing has been built around search.
Brands invested billions in SEO, paid search and content strategies designed to influence how consumers discover products and services.
AI is beginning to disrupt that model.
One of Cannes Lions 2026's most relevant sessions is titled "Winning the AI Discovery Era: Marketing to Minds and Machines." The premise is simple but profound: discovery is becoming increasingly AI-mediated. Instead of navigating links and results pages, consumers are asking questions and receiving recommendations directly from intelligent systems.
This creates a new challenge for marketers.
If consumers increasingly rely on AI systems to recommend products, services and information, what replaces traditional search optimisation? How should brands think about visibility in AI-generated recommendations? And who controls the recommendation layer?
These questions sit at the heart of what may become marketing's next major platform shift.
The brands that understand AI discovery early could gain a significant advantage over competitors still optimising for yesterday's consumer journey.
3. Can AI Scale Creativity Without Killing It?
Few sessions at Cannes Lions are attracting as much attention as "The Future of Creativity with Demis Hassabis."
The Google DeepMind CEO will discuss the company's collaborations with artists across film, games and music, and how those partnerships are helping shape AI's role in creative expression. According to the session description, the discussion will focus on how AI can support authentic storytelling while expanding human creativity rather than replacing it.
The timing is significant.
For the past two years, marketers have largely measured AI through the lens of efficiency. Faster content production. Lower costs. Greater output.
But efficiency and creativity are not the same thing.
As AI-generated content floods digital channels, differentiation may become harder rather than easier. If every brand has access to similar tools, creativity itself becomes a competitive advantage.
The debate unfolding at Cannes is not whether AI can create.
It is whether AI can help create ideas that people actually care about.
That distinction could determine the future relationship between technology and creativity.
4. Can AI Understand Brands Better Than Brands Understand Themselves?
Perhaps the most intriguing AI conversation at Cannes is not about creating content at all.
It is about understanding it.
One of the standout sessions in the Innovation Unwrapped programme is "The Anatomy of an Icon," featuring Aude Gandon, Chief Digital & Marketing Officer at The Estée Lauder Companies, and Nicola Mendelsohn, Head of Global Business Group at Meta.
The session explores how AI can analyse decades of creative archives to identify emotional signatures, sensory patterns and creative decisions that helped iconic brand ideas endure.
This reflects a broader shift happening across marketing.
For years, brands have used AI primarily to generate outputs.
Increasingly, they are using it to uncover insights.
Can AI identify recurring patterns across decades of campaigns? Can it explain why certain ideas resonate culturally? Can it reveal hidden connections between consumer behaviour and creative performance?
For brands sitting on years of customer and marketing data, these questions may ultimately prove more valuable than content generation itself.
The future of AI in marketing may be as much about understanding as it is about creating.
5. Trust vs Personalisation
The final debate may be the most important.
Trust.
One of the most anticipated sessions at Cannes Lions is OpenAI's "Advertising in the Age of AI," featuring Denise Dresser, Chief Revenue Officer at OpenAI, alongside CNBC's Julia Boorstin. The session explores how conversational environments are changing how brands engage audiences and how AI-native workflows could unlock personalisation at scale. It also examines what organisational capabilities are required as AI becomes an operating layer across marketing and creative functions.
The opportunity is enormous.
AI promises more relevant experiences, smarter recommendations and deeper personalisation than traditional marketing systems could ever deliver.
But it also introduces new risks.
How much personalisation is too much? How should brands maintain transparency when AI systems influence customer interactions? How can marketers balance automation with authenticity?
As AI becomes more deeply embedded into marketing workflows, trust may emerge as the defining currency of the next era.
The brands that win will not necessarily be those using the most AI.
They may be the ones using it most responsibly.
The Bigger Picture
Taken together, these five debates reveal a broader shift taking place across the industry.
The first phase of AI was about capability.
What can AI do?
The second phase is about application.
How can marketers use it?
The third phase, which Cannes Lions 2026 appears poised to explore, is about operating models.
How should brands, agencies and platforms organise themselves when intelligence becomes embedded in every stage of the marketing process?
That question will echo throughout Cannes this June.
The answers may shape the next decade of marketing.