Next in Media, spoke with S4 Capital founder and executive chairman Sir Martin Sorrell about the state of the ad business heading into a very uncertain year. Sorrell gave his take on Google's trial, the US Election, the future of ad agencies, and why the media business is a tale of two cities.

What's Really Holding Back Big Media From Doing More With Creators

Everything we know about the media, marketing and advertising business is being completely upended thanks to technology and data. We're talking with some of the top industry leaders as they steer their companies through constant change.