Japan’s Omnichannel Future: Can Advertising Catch Up With Consumer Behaviour?

Japanese consumers have already embraced the open internet. From connected TV and premium news to mobile apps and digital audio, audiences move naturally across channels throughout the day. Yet while consumers spend around 66% of their digital time across the open internet, only 34% of advertising investment follows them ( SeenThis Japan, Harris Poll ). So what’s holding advertisers back?

That question was at the heart of a recent panel discussion hosted by Magnite Japan, where leaders from Dentsu Japan International Brands, SmartNews, SMN Corporation and Magnite explored what it will take for the open internet to become a larger part of advertisers’ omnichannel strategies.

The Open Web’s Biggest Challenge Isn’t Scale – It’s Confidence

The open internet has changed dramatically over the past decade.

Premium connected TV inventory, trusted digital publishers, curated mobile applications and high-quality audio environments now form an increasingly important part of the programmatic ecosystem in Japan. Yet historical perceptions continue to shape investment decisions.

Stephen Leung, Associate Director, Dentsu Japan International Brands, believes the industry’s biggest barrier is no longer inventory quality.

“The biggest challenge isn’t the inventory itself. It’s trust—and making the value of the open internet easy to explain. The open internet has evolved significantly, but many advertisers and planners are still evaluating it based on perceptions from the past.”

If trust is one barrier, complexity is another.

Yusuke Kouga, Head of Ads Product GTM, SmartNews compared today’s media landscape to ordering at a restaurant.

“Walled gardens are like a set menu. You choose A, B or C and you know exactly what you’re getting. Programmatic is more like ordering à la carte—you can build exactly the combination that fits your objectives.”

The flexibility to combine premium streaming, digital news, mobile apps, audio and first-party data is one of the open web’s greatest strengths. At the same time, that flexibility can make programmatic feel more complicated than buying within closed platforms.

“The value of programmatic is still understood and fully utilised by only a limited number of advertisers and agencies today,” said Kouga.

As omnichannel media planning becomes more sophisticated, the industry’s challenge is no longer building better technology. It’s making sophisticated technology easier to use.

Measurement Must Evolve Alongside Consumer Behaviour

The panel also agreed that advertisers need a more complete understanding of campaign effectiveness. Today, many marketers still evaluate channels independently, even though consumers experience them together.

Magnite’s “Decoding the Connected Consumer” Japan Research showed 89% of Japanese consumers regularly engage with ad-supported open internet environments, while 46% use a second device while streaming, often searching for products or shopping online during viewing sessions. Rather than competing, these channels increasingly complement one another across the consumer journey.

Dentsu Japan International Brands’ Stephen believes this requires a fundamental shift in how the industry approaches measurement.

“Advertisers don’t simply want to know how one platform performed. They want to understand how every customer touchpoint contributes to overall business outcomes.”

Turning that vision into reality, however, requires overcoming several structural challenges.

As Lena Sakaguchi, Manager, SMN Corporation,  explained:

“Measurement fragmentation and optimisation speed remain two of our biggest challenges. Walled gardens operate within connected ecosystems, while the open internet depends on multiple partners working together.”

Privacy changes, evolving identity solutions and fragmented measurement have made collaboration more important than ever. Unlike closed platforms, the open web depends on multiple partners working together to measure performance across the customer journey, rather than within individual channels.

Beyond CPM: Defining Value Through Attention

If measurement is evolving, so too are the metrics that define advertising effectiveness.

For years, digital advertising rewarded efficiency through lower CPMs, cheaper reach and short-term performance. Increasingly, however, advertisers are asking a different question: not simply whether an ad was served, but whether it was actually noticed—and whether that attention ultimately influenced business outcomes.

The Attention Economy research by dentsu reflects this broader shift, arguing that as media consumption fragments, success will depend less on measuring impressions and more on understanding whether advertising captured attention and drove business outcomes.

Stephen believes Attention and Brand Lift should be viewed as part of a broader measurement framework rather than standalone KPIs.

“Attention and Brand Lift shouldn’t be the final destination. What’s important is demonstrating how those metrics connect to business outcomes and sales. When advertisers have that evidence, they’re much more willing to invest in new channels.”

That thinking is increasingly reflected across the industry. SmartNews’s Koga highlighted that users engage with the platform more frequently, spend longer with content and are less likely to multitask—characteristics that contribute to stronger Brand Lift outcomes. For DSPs, this also changes how campaigns are optimised.

“Performance optimisation has matured. The next challenge is how we incorporate quality into optimisation,” said SMN’s Sakaguchi. 

Rather than relying solely on clicks and conversions, DSPs are increasingly incorporating contextual signals, engagement metrics and Brand Lift Studies into optimisation models – moving the conversation beyond media cost towards media quality.

The Next Chapter Will Be Built Together

Throughout the discussion, one message remained remarkably consistent: no single organisation can solve omnichannel complexity alone.

Publishers create trusted environments. Agencies shape strategy. DSPs optimise campaign delivery. SSPs improve transparency and access to premium inventory. Realising the full potential of the open web will depend on how effectively those parts of the ecosystem work together.

As Sakaguchi concluded: “We need to create a new yardstick together.”

Looking ahead, Kouga believes emerging technologies such as Agentic AI could help remove one of programmatic’s biggest barriers – complexity. “If Agentic AI makes programmatic much easier for everyone to use, it can unlock the full value that programmatic has always had.”

Ultimately, the discussion pointed towards a broader ambition for the industry. As Stephen reflected: “I hope we can move the conversation beyond competition between walled gardens and the open internet, and instead focus on growing the market as a whole.”

Consumers in Japan have already embraced an omnichannel world. The opportunity now is to ensure advertising evolves alongside audiences. If the industry can simplify how premium media is planned, measured and activated – and establish common frameworks that better demonstrate business outcomes – Japan is well positioned to unlock the full potential of its premium open web ecosystem.