Resumen: In this chapter, we will address the evolution experienced by the industry in the battle for audiences. This wil require, first, to review the economic ratinale for the conquest of time in traditional TV networks. We will point out some ideas about digital audiences and appropriate measurement systems that come as a result of digital development. Finally, we will note the need to advance in the knowledge of the audience from a more qualitative perspective. We no longer deal with the battle for time of the viewers, but the battle for their attention, for engagement with them.