Fundamentally, CMOs have two concerns when it comes to media: value and impact.

It needs to come at the right cost. And it needs to work.

Historically, there’s been a line in the sand between media and creative. This was OK because they were very distinct pieces of the marketing puzzle that addressed these CMO’s concerns: Media agencies had the buying power to command better prices and the infrastructure to execute; creative agencies knew how to make the content that determined if media actually succeeded at making an impact.

For a long time, there has been an ebb and flow between specialization and integration between these functions. In recent years, many have evangelized the need for greater integration between media and creative. However, two conflicting forces have often hindered integration from taking place.

On one hand, the diverse media landscape and resultant battle for consumer attention has made the need for integrated thinking tantamount in importance. On the other, the rising tide of programmatic buying technology has made the planning, buying and optimization of media increasingly data-driven and operational in nature.

This conflict is why in 2018, we’ll see a new dividing line with media strategy and creative on one side, and media execution on the other.

Media agencies tend to have established infrastructure, vendor relationships and operational expertise. They tend to be full of binary thinkers and linear structured bureaucracies that serve the execution of media plans very well.

Media buying, meanwhile, has become more and more commoditized. Many brands deem the act of executing media buys so undifferentiated an exercise—and are so frustrated with the lack of transparency that exercise has been performed with—that they’ve brought the process in-house. Others continue to rely on media agencies with the infrastructure to efficiently execute.

But integration is critical for creating ideas that deliver impact.

The best ideas come from collaboration between media and creative. This morning I had coffee with the CMO of a challenger brand whose business I am trying to win. He said to me, “We don’t have the same budget as our competitor. We need to figure out how to show up differently.”

Showing up differently requires creative thinking. It requires really understanding the human beings we call consumers, and it requires imagination. In other words, the things creative agencies are really good at. There are a million roads to market. The best ones don’t just reach consumers, they create value for them. Picking the right path to make the most impact should be informed by data, but ultimately it is incredibly subjective.

Today, ideas and the delivery of those ideas are inextricably linked. Simply throwing a TV spot over the fence doesn’t work anymore. People are more than just harder to reach—they are actively skipping, blocking and avoiding ads. We can’t just rely on counting impressions—we have to make sure we are making them.

Even predicting the impact a video will make when it is delivered on “Sunday Night Football,” Hulu, Instagram, Facebook, YouTube or Snapchat is incredibly subjective.

Media agencies are very good at spreadsheets, but not at subjectivity.

Creative agencies are not only comfortable with subjectivity, they are innately collaborative. The inherent nature of their work is a mindmeld of diverse perspectives. Planners and art directors and writers and technologists come together to forge the raw materials of insights, imagination and possibility into ideas that hold the potential to inspire, engage, persuade, and, sometimes, reshape the fortune of brands.

Which is probably why the two most recent new clients we’ve won at Mosaic have asked our creatives to create a media strategy across paid, owned and earned channels and partner with their existing media agencies to execute the buy.

To many, the notion of a creative shop leading media strategy may seem unconventional, perhaps even radical. Well, the world has changed and one thing is certain not to lead the way in 2018—and that is the status quo.