Digital entrants have changed the competitive landscape for advertisers and media. Over the past decade, media agencies have grown more rapidly than the media market as a whole, securing a larger share of the value generated in the advertising industry. We develop a process model describing how these agencies have altered their business models over a decade. We discuss three separate stages in this innovation process, labelled business model innovation (BMI) awareness, business model exploration, and business model exploitation. We find and document how different building blocks of the business model are a focal point of innovation in each stage of the BMI process. Our findings offer a way for the media industry to understand the transformation of media agencies.